Infinity Train: Book Three — Cult of the Conductor Review

Infinity Train Book Three has concluded but more is sure to come

Infinity Train Book Three: Grace comforts a crying Hazel
(Image: © WarnerMedia)

What to Watch Verdict

Another half hour of Infinity Train Book Three is here and while I am on the edge of my seat waiting for the conclusion next week, these three episodes hit even harder than the first five. This season so far is an absolute must see!


  • +

    Compelling character development

  • +

    Continues to expand our understanding of the Train

  • +

    Deeply moving

  • +

    Tells so much in the unspoken moments


  • -

    Too short

  • -

    Feels unfinished

SPOILER WARNING: This article contains spoilers for all of Infinity Train. 

When the pilot for Infinity Train first went live back in 2016, the show immediately garnered a huge following with over a million views in the first month. Since then, it’s gained over 5 million views, setting it almost half a million views above the second most viewed pilot on Cartoon Network’s channel. However, it would be two years before Cartoon Network confirmed the series had been greenlit and another year before the first season would premiere. The first two books, along with ten shorts, aired on Cartoon Network garnering critical acclaim and an Annie Award nomination. Now, the series faces another big change, as Infinity Train: Book Three is available exclusively on HBO Max. 


HBO Max logo

(Image credit: HBO Max)

HBO's new streaming service, HBO Max gives you access to all of HBO's content and so much more! With select content from TNT, TBS, Cartoon Network, and more, as well as original content, HBO Max is the only place to watch Infinity Train: Book Three. It also has Book One and Two available for those who need to catch up or want to go back for another viewing.

What's happened so far...

Infinity Train Book One

(Image credit: Cartoon Network)

Infinity Train Book One: The Perennial Child follows Tulip, a thirteen year old girl whose trip to a game design camp gets canceled when a miscommunication between her recently divorced parents leaves no one free to take her to the train. Deciding to take herself, Tulip ends up taking the wrong train entirely, leading to her journey on the Infinity Train. Tulip finds a glowing number on her hand that changes based on the choices she makes aboard the Infinity Train. Over the course of Book One, Tulip makes new friends and enemies, all while being forced to solve both the mysteries of the Infinity Train and her own inability to move past the divorce of her parents. 

Infinity Train Book Two

(Image credit: Cartoon Network)

Infinity Train Book Two: Cracked Reflections follows Lake (formerly known as MT,) the Chrome Car reflection of Tulip. Lake befriends Jesse, another human stuck on the Train and Alan Dracula, a deer-like creature created by the Train. As Lake tries to evade the Mirror Police, she and Jesse team up with the goal of escaping the train together - something that proves to be quite difficult since Lake doesn't have a number. Having to face off against a pair of Mirror Agents and the Apex, a tribe of anarchist kids who believe the Infinity Train is theirs to do with as they please, Lake and Jesse's adventures cover themes of identity, friendship, and peer pressure. 

Book Three: Cult of the Conductor

Infinity Train Book Three

(Image credit: WarnerMedia)

Divided up into five 12 minute episodes, Infinity Train Book Three: Cult of the Conductor began streaming on August 13, 2020. Three more episodes were added on August 20 and the final two followed on August 27. The episodes titles are:

The Musical Car
The Jungle Car
The Debutante Ball Car
Le Chat Chalet Car
The Color Clock Car
The Campfire Car
The Canyon of the Golden Winged Snakes Car
The Hey Ho Whoa Car
The Origami Car
The New Apex

Book Three opens with the Apex, led by Grace and Simon, raiding the Musical Car. The pair encourage the rest of the kids to wreck the Musical Car, bringing them gifts which Grace makes a big production of accepting. Each time Grace speaks with one of the younger kids, she puts on a warm smile and a kind tone, but the moment one of the kids refers to a denizen as a person, she reverts to harsh.

The kids move on to the next car, but before they can finish, the car begins to shift. Simon gets trapped and Grace stays behind to save him. Although the pair get separated from the rest of the Apex, Grace insists they treat it like a vacation until they can get back to their car. Despite her carefree attitude or her harsh moments, it's clear Grace genuinely cares for each of the passengers - something that was hinted at when Jesse left the Train in Book Two.

Grace and Simon on vacation from the Apex

(Image credit: Warner Media)

Although it was clear from their introduction in Book Two that Grace and Simon had both been on the Infinity Train for a long time, some of their past start showing as the pair work to get back to the Apex car. They make their way through the cars between themselves and the rest of their crew, only to stumble across another passenger, a little girl named Hazel.

Tuba protects Hazel

(Image credit: Warner Media)

Unlike other passengers, Hazel's number doesn't glow. Simon and Grace think that One-One turned it off to hide Hazel from the Apex. Complicating matters further, Hazel is in the company of Tuba, a massive purple gorilla with a pair of tubas wrapped around her shoulders. Grace convinces Hazel to come with them and after some fuss, agrees to take Tuba along. 

Once more, the little details are where this series shines. Grace bonds with Hazel, but each step she takes brings her number down a little more. Meanwhile, Simon grows more and more impatient with the Train, Tuba, and Grace's nonchalance. We even get hints of jealousy as he pushes Grace to ditch Tuba and hurry back to the Apex.

Simon and Grace

(Image credit: Warner Media)

As Grace, Simon, Hazel, and Tuba travel through cars, Hazel encourages Grace to open up more, while Simon's focus keeps coming back to taking out Tuba. Although Simon and Grace were antagonistic and unsympathetic in Book Two, Book Three shows their insecurities and the trauma in their pasts. Further, it highlights how Amelia taking over the Infinity Train impacted the other passengers, as well as the denizens.

Simon reveals he arrived on the Train when he was only ten, alone and confused, with no video from One-One explaining that he needed to reduce his number. Grace too reveals she arrived on the train as a young child, some time before Simon. Grace even had a run in with Amelia who she believes to be the true conductor. Upon meeting Simon, the pair learned to depend on each other before building the Apex.

Meeting the Cat again

(Image credit: Warner Media)

While Hazel continues to encourage both Grace and Simon to complete the different car challenges, a run in with another denizen further drives the wedge between the pair. The Cat returns and it is revealed that she was Simon's denizen when he first arrived on the Infinity Train. What's more, she abandoned him after months of trying to help him - something that provides a basis for his hatred of the denizens of the train.

Grace admits to Simon that her number is going down and she didn't want him to think less of her. Simon affirms that he is with her no matter what and they figure out the Cat's Chalet Car. Simon looks back at the Cat once more, bidding her au revoir with a look of regret.

Simon works with Tuba

(Image credit: Warner Media)

All this culminates in The Color Clock Car, where Simon and Tuba are forced to work together to solve a puzzle. Just when it seems like Simon is opening up to Tuba, he takes the opportunity to separate her from the party. When he returns without Tuba, Simon informs Hazel that she's gone and the little girl breaks down into something not so little and not so human. 

Has Hazel been a denizen this whole time? Or is there something deeper going on here?

Grace comforts Hazel

(Image credit: WarnerMedia)

Picking up where we left off, Grace overcomes her shock quickly and comforts Hazel. This was a huge pivotal moment for Grace, who up until now, has had an extreme dislike for Nulls. Although she knows that Hazel is a denizen, not a passenger, Grace understands that she is hurting and scared, and she puts aside her prejudices to comfort her. 

Hazel, understandably, jumps right into the first three stage of grief: denial, anger, and most heartbreaking, bargaining. I'll be honest, I wasn't expecting to be in tears in the first few minutes of this episode, but hearing this little girl plead for Tuba to come back broke me. She promises to be really, really good if she could just have her friend back. Isabella Abiera, who is a small child herself, is to be commended for her absolutely heart-wrenching performance.

Hazel tries to find a spot for Tuba

(Image credit: WarnerMedia)

After getting Hazel to calm down, Grace promises to keep her safe by not letting Simon know what she is. They regroup with Simon in the next car, the Campfire Car, where Hazel asks to have a funeral so she can say goodbye to Tuba. Although Simon puts up a fight, Grace convinces him that it's important to help Hazel move on. They search the Campfire Car for the right spot, finally settling on a tree so Tuba can see the sky.

Hazel sings Tuba's song

(Image credit: WarnerMedia)

Hazel says a few words for Tuba, concluding with, “Thank you for being with me Tuba. I’m going to keep loving you like you’re still here.” Grace says a few words as well and then Hazel sings the song that Tuba sang to her before. Hazel cries, Grace cries, everyone watching cries. 

It was a deeply moving moment to say the least. While I have my complaints about the timing for delivering these episodes, I must admit, having a week to really process this episode might not be such a bad thing. This series covers some really deep, emotionally intense themes, but this particular scene shook me hard.

Grace, Simon, and Hazel see Amelia's number

(Image credit: WarnerMedia)

But the show must go on and so it did. Moving on to the next car, the Canyon of the Golden Winged Snakes Car, the trio run across Amelia. Initially, Grace distrusts Amelia and insists that they run from her. However, Simon can't seem to accept Grace's reasoning. Amelia has the biggest number they've ever seen, after all. He confronts Grace only to be shot down and pushed away.

It's in this moment that you can just hear the unspoken apologies. After the pair pull apart, both have a moment where an apology is clearly on the tips of their tongues, only to be bit back. The rift between Grace and Simon is palpable and growing with each moment.

Simon confronts the Cat

(Image credit: WarnerMedia)

Seeking answers, Simon returns to the Le Chat Chalet Car and confronts the Cat. The Cat, who we find is named Samantha, tries to reconnect with Simon, despite his abrupt demands and need to fight. She explains that she didn't leave him, but was running and thought he was right behind her. When Simon insists that her explanation just isn't good enough, Samantha, voiced by the phenomenal Kate Mulgrew, insists, “I am who I am, Simon. I can’t give you more than that.”

This highlights another theme that is prevalent this season. When we first met Grace and Simon, the two were mostly on the same page about everything. Their only real conflict was over Simon's lack of respect for Jesse, who Grace felt was just misguided. However, the further we delve into Book Three, the greater the rift between Grace and Simon grows, largely because neither accepts the other for who they are. Simon lashes out at Samantha because Grace isn't behaving "like she's supposed to." 

Samantha provides Simon with the tools he needs to see what's really going on in Grace's mind. She also warns him that, "We shouldn’t always know what’s in a person’s mind, especially those we love." It's clear Simon doesn't care about the warning as Samantha watches him walk off into the storm.

Amelia makes eggs for Hazel and Grace

(Image credit: WarnerMedia)

Meanwhile, Grace and Hazel wake only to be attacked by one of the Winged Snakes. Amelia saves them and offers to make them eggs. Despite Grace's distrust, Hazel grows fond of Amelia, but when Simon returns, he attempts to fight Amelia. In the tussle, it comes out that Amelia is the person they believed to be the true conductor. They move on to the next car, the Hey Ho Whoa Car, where Amelia tells them her story.

Grace seems to process everything Amelia says, while Simon rejects it, insisting that Amelia lost her way. Before the two can fight it out, Hazel reverts to her turtle form and though Grace attempts to convince everyone that she didn't know, Simon's distrust only grows.

Simon sees Grace's memories

(Image credit: WarnerMedia)

Using the tools provided by Samantha, Simon looks into Grace's memories while she sleeps. Seeing that Grace insisted on keeping Hazel's secret from him, Simon was left in tears, clearly feeling betrayed.

(Image credit: WarnerMedia)

The second to last episode, The Origami Car picks up with Grace waking up to find everyone upset. She tries to smooth things over, but Hazel insists that she won't be going with Grace. She insists that the Apex are afraid of her and chooses instead to go with Amelia.

(Image credit: WarnerMedia)

Grace pleads with Hazel to come with them, much to Simon's dismay, but Hazel leaves with Amelia all the same. As they move on to the next car, the titular Origami Car, Grace and Simon fight over Hazel. Simon loses his temper and throws Grace into her own memories - something we all knew was going to happen when Samantha warned him of the danger.

(Image credit: WarnerMedia)

Trapped inside her own memories, Grace first experiences the ballet recital she had told Hazel about earlier. We see the other children bully her and Grace respond in kind, instigating a fight between the other girls. Moving on, we see the moment when Grace ends up on the Infinity Train, shortly after she is picked up for shoplifting. Grace admits she just wanted to be noticed before the Train appears before her younger self, prompting her to board. Simon shows up and joins Grace as she moves forward through her memories.

As expected, her early days on the Train are shown to have been terrifying; however, when Grace comes face-to-face with Amelia the first time, she stops the memory and insists that it wasn't right. Simon challenges Grace as she corrects the memory, prompting Grace to sum up their conflict perfectly: “So my memories are real until you don’t like them?”

(Image credit: WarnerMedia)

Despite their conflict, we keep moving through Grace's memories, leading to her meeting and subsequently saving Simon. She tells him what she thinks he wants to hear and the two form the Apex together. This only prompts Simon to challenge Grace again. He forces her to see the moment when she told Hazel they could keep her identity secret and Simon declares that everyone lies to him: Amelia, Grace, and Samantha. He then traps her in her memory and leaves her to die.

Grace doesn't die, however. Instead, she faces her fears and admits to her mistakes. She confesses to her memory of Hazel and to herself why she lied. All the while, we see Grace's number dropping as she becomes more and more tangible. Finally, having taken responsibility for her wrongs, Grace wakes herself.

(Image credit: WarnerMedia)

What follows Grace waking was a bit grotesque, even for a series such as Infinity Train. Grace finds her memory tape continuing to flow from her head and literally rips it out in horror, gagging as it comes out coated in some sort of visceral goop. She pulls herself together and moves on, finding a trail of crushed origami cranes leading to the door. 

Rather than moving past them, Grace stops to smooth out their wrinkles and refold each crane Simon had crushed. Upon seeing her reflection in one of the cranes, Grace wipes the Apex symbol off her cheeks. She returns to the Apex car, ready to face her mistakes.

(Image credit: WarnerMedia)

What Grace finds in the Apex car shocks her, but comes as no surprise to the audience given Simon's deterioration this season. The younger members of the Apex call Grace a Void and report her to Simon, whose number is now climbing up his neck. Simon explains that a Void is a leader no longer fit to lead and insists that she gets the Wheel, like so many Nulls had before.

(Image credit: WarnerMedia)

The two fight while the rest of the Apex hide, but with each exchange, Grace's number drops and Simon's increases. Just when Grace could win and let Simon fall, she saves him, pulling him back onto the Train. Simon questions why she would do that and then kicks her off the Train, much to the horror of the younger kids watching. Simon's number covers his face as he clearly suffers a mental breakdown.

(Image credit: WarnerMedia)

Grace, however, is saved in much the same way as she saved herself. By attempting to repair harm instead of inflict it, she restores the paper cranes from the Origami Car, and those same cranes fly to her rescue, carrying her back to the Train. Meanwhile, Simon meets a grisly fate as one of the Gohms sucks the life from him, leaving only a bit of sludge. Despite how he turned on her, Grace sobs over the remains of her friend.

(Image credit: WarnerMedia)

The episode concludes some time later with an inspirational speech by Grace to the rest of the children in the Apex. She insists they can no longer be the Apex, but that they will figure it out together - a promise that sets all of their numbers into flux.

What comes next?

(Image credit: WarnerMedia)

Book Three of Infinity Train closes on that scene, leaving much more unresolved than the previous books. While this season went above and beyond the previous two, both One and Two stood on their own and either could have concluded the series. It's rare to find such concise and impactful storytelling, especially in children's programming.

This series has covered some pretty intense themes, from divorce to peer pressure to identity. This season delved even deeper, confronting the lies we tell to others and to ourselves. We saw the deep impacts childhood trauma can have that ripple out for years to come. We had our hearts ripped out and we watched as two people with similar trauma take completely divergent paths.

While I've spoken at length over the importance of shows like Steven Universe and She-Ra and the Princesses of Power in the evolving landscape of entertainment for children and teens, Infinity Train is at the top of the list for the way it handles trauma and working past it.

My only real complaint this season is the length. While both Book One and Book Two worked as standalone miniseries. This third book didn't stand as completely on its own and left some significant unresolved plotlines. Despite that, I cannot recommend this series more and will wait eagerly for Book Four.