Six Four: ITV1 release date, cast, plot, trailer, interviews, episode guide and all about the crime thriller

Six Four stars Kevin McKidd and Vinette Robinson in the new ITVx thriller.
Six Four stars Kevin McKidd and Vinette Robinson in the new ITVx thriller. (Image credit: ITV)

Six Four is a crime thriller on ITVX that sees a police detective trying to find his missing teenage daughter in this drama based on Japanese bestselling thriller by Hideyo Yokoyama. 

Played by Grey’s Anatomy star Kevin McKidd, Chris O’Neill is a serving police officer whose own daughter’s disappearance leads him to the unresolved case of a missing local girl called Julie Mackie. As Chris delves deeper into Julie’s case he uncovers evidence of errors, corruption and unbridled ambition. Meanwhile, his wife Michelle, a former undercover officer played by Vinette Robinson, decides to look for their daughter alone, leading her deep into the criminal underworld.

“I never take for granted the privilege of being an actor and the chance to become characters like Chris O'Neill, a hard-working serving police officer, whose teenage daughter has gone missing in Six Four,” says Kevin McKidd. “I'm delighted to be returning to my native Scotland and to be partnering Vinette Robinson as my on-screen wife, Michelle.” 

Here here’s everything you need to know about the compelling crime thriller Six Four

Kevin McKidd takes the lead role in Six Four.

Kevin McKidd takes the lead role in Six Four. (Image credit: ITV)

Six Four release date

Six Four is a four-part series that arrives on ITV1 in October 2023. It previously launched on ITV’s new streaming service ITVX on Thursday March 30 2023. We'll update with any US or international release dates when we hear.

Six Four plot 

In Six Four, Chris O’Neill (Kevin McKidd) is a police detective who is left reeling by the news that his own teenage daughter has disappeared. Then he is approached by a journalist who tells him to revisit the infamous unsolved case of missing local girl Julie Mackie because fatal mistakes were covered up. 

As Chris re-examines the case, he uncovers a long list of errors and firm evidence of wrongdoing. Meanwhile, his wife Michelle (Vinette Robinson), a former undercover officer, decides to take matters into her own hands and find their daughter herself. But the clues expose the close ties between the criminal underworld and those at the very top of the political establishment. 

But just as Chris and Michelle get close to the truth another girl goes missing — this time the daughter of the Justice Minister who was on the brink of an election victory. The kidnap has striking similarities to Julie Mackie’s case, so is the past repeating itself? 

There's tense drama in Six Four.

There's tense drama in Six Four. (Image credit: ITV)

Is there a trailer for Six Four? 

Yes a trailer for Six Four has now been released by ITV which starts with Kevin McKidd's Chris O’Neill showing a witness an identity parade. Take a look below...

Six Four cast: who's who in the crime drama series

Six Four cast — Kevin McKidd on playing Chris O’Neill

Kevin McKidd plays police detective Chris McNeil whose teenage daughter disappears. 

Kevin told us:  "It’s one of those dramas where you’re going to have to pay attention because it’s complex and dense, but also compelling and entertaining. You’ll be on the edge of your seat!

"Chris is having a midlife crisis, and he’s not feeling connected to his wife or his work. But when the Julie Mackie case bubbles up at the same time as his daughter’s disappearance, it reignites him as a detective and a family man.

"He has been very much stuck at his desk, doing the bare minimum to get by and living in the shadow of his brother, Philip. But when the journalist starts asking questions about Julie Mackie, he puts himself in real jeopardy to seek out the truth, which always finds its way out!

"The novel is a huge hit in Japan, but the show’s writer, Gregory Burke, has taken the core elements and put his own spin on it. Glasgow is a great setting, as it’s got a messy and sustained history of corruption and violence."

* Kevin McKidd previously played Tommy in the 1996 film Trainspotting and went on to star as Count Vronsky in the ITV series Anna Karenina. He’s also appeared in After Life, Rome, Percy Jackson & The Lightning Thief, Star Wars: Rebels and Station 19. Kevin is well known for his role as Dr Owen Hunt in Grey’s Anatomy

Kevin McKidd leads the cast in Six Four on ITVX.

Kevin McKidd leads the cast in Six Four on ITVX. (Image credit: ITV)

Kevin McKidd in Grey's Anatomy.

Kevin McKidd as Dr Owen Hunt in Grey's Anatomy. (Image credit: ABC/Sky)

Kevin McKidd in 1996 film Trainspotting alongside Ewan McGregor and Johnny Lee Miller.

Kevin McKidd (second from right) in 1996 film Trainspotting alongside Ewan McGregor and Johnny Lee Miller. (Image credit: Channel 4/Film Four)

Vinette Robinson on playing Michelle O’Neill

Vinette Robinson plays Chris' wife Michelle O’Neill whose equally frantic about her daughter going missing.

Vinette told us: "I love that Six Four has got the classic elements of a political crime thriller, so it’s twisty-turny and there’s investigation into power structures. But at the heart of it, is the relationship between Chris and Michelle, and their struggles are very relatable.

"Chris and Michelle are a couple at a crisis point, and when Michelle takes matters into her own hands and goes back into her old life, which has largely been kept secret, it adds even more pressure to their marriage. 

"As Michelle’s life as an undercover cop is reactivated and it forces her to face some truths in her relationship, and in herself."

* Vinette Robinson previously played Tracy in the 2003 series Between the Sheets. She’s since been in Hope Springs, Waterloo Road, Doctors and Sherlock. She starred as Nicola Daniels in The A Word and played civil rights campaigner Rosa Parks in an episode of Doctor Who. She’s also had roles in A Christmas Carol, Star Wars: The Rise of Skywalker and the critically acclaimed movie Boiling Point with Stephen Graham. 

Vinette Robinson as Michelle O'Neill.

Vinette Robinson as Michelle O'Neill. (Image credit: ITV)

Vinette Robinson plays Michelle O’Neill in Six Four.

Vinette Robinson plays Michelle O’Neill in Six Four.  (Image credit: Getty)

Vinette Robinson as Rosa Parks in Doctor Who.

Vinette Robinson as Rosa Parks in Doctor Who. (Image credit: BBC)

Who else is starring in Six Four? 

The Six Four cast also includes Brian McCardle (Time) who plays private security officer Bill Martin, Andrew Whipp as Assistant Chief Constable Philip O’Neill and James Cosmo as former lawyer Jim Mackie, while Richard Coyle (Fantastic Beasts: The Secrets of Dumbledore), Lorne Macfadyen (Tina & Bobby) and Alex Ferns (EastEnders, Danny Boy) plus newcomers Iona Anderson, Andrew O’Neill and Nilani Chetty also star.

James Cosmo says: "I just thought the content was so intriguing. All these dark political things are going on, and it’s very well written. Reading the character they asked me to play, in the first episode, you think, “Oh, this poor guy, his daughter's gone missing.” But by the end, you go, “Oh, my God, what is going on here?” So I thought, “If it intrigues me, it will intrigue the audience.”

Bill Martin says: "What attracted me Six Four is a myriad of different components coming together because it is a collaboration. The script written by Gregory Burke is top-class. It's interesting and with a lot of plot twists and turns and no characters are stock characters, they all read as specific individuals. And it's unpredictable; I found it fascinating."

James Cosmo as former lawyer Jim Mackie.

James Cosmo as former lawyer Jim Mackie. (Image credit: ITV)

Bill Martin in Six Four, wearing a suit and looking serious.

Bill Martin in Six Four. (Image credit: ITV)

Alex Ferns (on far right) in Danny Boy.

SIx Four star Alex Ferns (on far right) in Danny Boy. (Image credit: Gareth King (BBC).)

Six Four episode guide

Here's a brief lowdown on all four episodes of Six Four....

Episode 1
DC Chris O’Neill is approached by a journalist about a cold case involving a missing girl. His own daughter is also missing, and his wife Michelle goes to London to search for her.

Episode 2
Pauline Wallace receives a ransom call. Chris discovers a link between Annabel’s kidnapping and the supposed cover-up in the Julie Mackie case and Michelle confronts Piers.

Episode 3
An unexpected visitor confronts Chris with the consequences of Michelle’s secrets. A visit to Gary McLean’s killer brings Chris closer to the truth and Annabel faces her captor.

Episode 4
Michelle returns to Scotland and accompanies Chris in search of Annabel. Robert and Mackie face off as the truth behind Julie Mackie’s disappearance threatens to come out.

DC Chris O’Neill gets into hot water.

DC Chris O’Neill gets into hot water. (Image credit: ITV)

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Nicholas Cannon
TV Content Director on TV Times, What's On TV and TV & Satellite Week

I'm a huge fan of television so I really have found the perfect job, as I've been writing about TV shows, films and interviewing major television, film and sports stars for over 25 years. I'm currently TV Content Director on What's On TV, TV Times, TV and Satellite Week magazines plus I previously worked on Woman and Woman's Own in the 1990s. Outside of work I swim every morning, support Charlton Athletic football club and get nostalgic about TV shows Cagney & Lacey, I Claudius, Dallas and Tenko. I'm totally on top of everything good coming up too.

With contributions from
  • Senior Writer for TV Times, TV & Satellite Week, What's On TV and