The episode marked the first time Zoe had been reunited with husband Max Walker, played by Jamie Davis, since her exit episode all the way back in 2016.
And while fans were clearly delighted about the return of one of their favourite characters, most viewers appeared even more overjoyed about the way their storyline ended up.
As Saturday's episode drew to it's conclusion, viewers witnessed porter Max eventually follow wife Zoe onto a plane, in order to give his marriage to the doctor another go.
And while fans were aware of Zoe's return to the soap, the news that Max would be leaving Casualty for good was kept under wraps until the episode aired.
Nor did they know that the beloved couple would be heading off for a brand new start together - meaning two of their favourite characters would be leaving the show.
But despite the sad exit of the characters, most fans simply seemed delighted that the pair had finally found their 'happy ever after' together, after some tough times together.
One fan wrote, "Really happy at the ending with max and Zoe!! Meant to be #Casualty"
While another viewer said, "So over the moon Dr Hanna n Max are back together, such a romantic ending #Casualty"
Another fan commented, "So nice to see Max and Zoe get their happy ending! #casualty", while a fourth wrote, "Tonight’s @BBCCasualty has made me so happy! I love a good romance! #maxandzoe #Casualty
But other viewers seemed to be left heartbroken by the bittersweet twist, appearing devastated that neither Max nor Zoe would be staying in the soap.
One wrote, "Could you not have brought Zoe back rather than Max leave??? @sarker @BBCCasualty #Casualty", while another said, "Absolutely chuffed and gutted at the same time, please come back! #Casualty #Zaxforever"
A third fan commented, "So has #Max left #Casualty for good..?? I was hoping i dreamt that episode last night"
While a fourth said, "MAX!!!! I have actual tears falling to the floor #Casualty", and another viewer said, Noooo Max is leaving, he was one of my favourite characters"
But others admitted that there were simply going to miss both characters, who have become popular over the course of their run on the series.
A viewer said, "That #Casualty made my heart so happy. I will miss #Zax so much."
What did you think of Max and Zoe's exit? Were you happy for the couple - or will you miss them?
Casualty returns to BBC One on 20th January at 9pm.
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