Silent Witness season 27 episode 10 concludes the series in dramatic style with a big development for Nikki and Jack. It opens with DI Steve Tudor (Neil Pearson) asking Mrs Perry, the wife of one of the victims, about Terry, who she believes is the killer. "One of Adam's lads" she replies. She explains that she knows her husband was a bad man and he recruited Terry as a rent boy when he was sleeping rough at the station. When Terry became older, he became Adam’s enforcer. The day he vanished Adam was looking for Terry. The widow reveals she hasn't disturbed Adam’s office in all this time.
His widow reveals she saw Terry and he said Adam had got what was coming to him. She reveals that Terry knew the station inside and out.
The police put everything into finding Terry. But they quickly discover he's not the killer, he is in fact the second victim.
The police dig into their files and find a video of Adam being attacked before he was murdered, with Terry coming to help. They have a very grainy image of the attacker, but they can see the coat he's wearing.
Nikki is tired and needs a Jack hug!
Nikki and Jack visit Malcolm, who says when he was station coordinator he'd clash with Steve. Malcolm said he was smeared by the police, who said he was too close to the runaways in the station. He says they wanted him out of the way so they could clear the station of the runaways. Is he telling the truth?
They think they have the "killer's" green coat amongst all the evidence from the King's Cross scene. There's blood on the jacket which matches a drug dealer called Dean in Sheffield, who was stabbed to death the day before Adam was attacked. Confused yet?! It appears Dean was murdered by the killer in Sheffield before he fled to London where he then carried out the rest of his crimes.
Nikki says she wants to go to Sheffield to look at the PM report. A builder who worked at the station recalls a young worker who kipped in the station and pinched a hand cart, sounds like it could be the killer. Had a northern accent, all roads lead to Sheffield…
The young lad attacked his co-workers and they called the police. But the lad fled the police. And who should be one of the cops he fled from but dodgy Keith from the previous episode!
Shelia interviews Keith. We discover his cop partner was Russell Drake, whose body we saw at the end of the previous episode after he’d arranged to meet Keith to talk about King's Cross.
Keith says he now works in security. Shelia finds it strange that Keith hasn't even asked if it has anything to do with the bodies at King's Cross. Shelia learns Russell's body has been fished out of a canal.
In Sheffield, Nikki and Steve meet a cop to talk about the drug dealer's death, who they think is the King's Cross serial killer’s first victim. She recalls the teenage son of the woman the victim was in a relationship with was seen in the vicinity, but the cop dismissed him as a suspect. Steve doesn't look impressed!
Jack and Gabriel perform a PM on Russell's body. Gabriel concludes that someone tried to make it look like Russell had drunk himself to death, but he hadn’t. And the last phone call he made was to Keith, so the police go to arrest Keith.
In Sheffield, Nikki and Steve visit Mary, the mother of the teenage suspect, Carl. Carl was in the army! They look at a photo and it's the man at Keith's security headquarters where Jack is!
Carl flees to the woods where he meets Keith. "You’re a monster, but you're my monster," Keith tells Carl, after he admits to killing the King’s Cross victims as "practice".
Keith shoots King's Cross serial killer Carl! Keith is arrested. Jack goes to see Nikki and pretends he's there for an advert for a lodger.
The pair sit down and Jack presents Nikki with a ring. “I can’t imagine a day without you, I can't. Will you marry me Nikki?”
And she kisses him and says “Yes!”.
