The Pact series two is well underway on BBC One and for those who have already binged all six episodes and need a debrief following the shock twist finale, we've got you covered.
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The series stars Rakie Ayola as social worker Christine, a mother of three children trying to move on from the tragic death of her son when a stranger named Connor arrives in town, claiming to know a dark secret.
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What happened at the end of The Pact season 2?
The final episode saw the Rees family's life upended by a shocking revelation about Christine.
During a tense meal with her children Will, Jamie and Megan and Megan's new husband, Gethin, Christine was forced to confront her past, admitting that her late son Liam wasn't her biological child.
It was revealed that Christine's friend and former colleague Kate had a pregnant client who was struggling with addiction issues and living in a squat many years ago. This was Liam's mother and after giving birth to her son, she bolted. With Kate panicking, Christine decided to step in to help and having suffered an unhappy childhood herself, took Liam in and claimed him as her own.
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While Christine's husband, Harry, wasn't too happy with the situation, he supported his wife until it became too much for him and their relationship subsequently broke down.
Mali Ann Rees, Lloyd Everitt and Aaron Anthony as Megan, Will and Jamie
Christine's new son-in-law then asked: "What about the others?", pointing out that if the social worker could lie about one child, what's to say Will, Jamie and Megan weren't her real children either?
While Christine tried her best to convince her three children that they were indeed her own, the trio weren't convinced and began to recall memories from their past. "This isn't a family. It's a cult," said a distraught Megan, while Will added that he'd never seen a photo of Christine while she was pregnant.
Later on, Christine's client Kayla arrived at the house with her baby and made a shocking confession. She told the social worker that she had been with Liam when he died and when he asked her to bring him "something strong", she injected him with the drug dose that led to his death.
Jordan Wilks as Connor
Angry after learning the truth, Christine waited for the right moment before disappearing to the cliffside along with Kayla's baby.
Megan, Will and Jamie soon followed after her and upon finding her on a bench overlooking the sea, Megan rescued the infant.
When their backs were turned, Christine threw herself off the cliff, leaving behind her three heartbroken children and her phone containing her admission to injecting a lethal dose of GHB into Connor's drink.
Handing the phone over to the police, Gethin said that had Christine lived, her children would never have let her take the sole blame for Connor's death.
"She's given us a way out," said Megan. "One last lie."
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