This week's Law & Order: UK picks up where last week's episode left off, with Sam Casey as a suspect in the death of Finn Tyler. As the investigation begins, new Major Investigations Unit boss Leyton is immediately suspicious of the apparent suicide, which makes Ronnie Brooks - who would do his job calmly if he were on fire - look sidelong at his partner, Sam. Sam still seems like he's in a daze. He's not helping himself at all.

When Sam returns to the MIU bullpen, Ronnie wants to know what he was doing before the death, but doesn't get an answer. Despite the fact that the young Detective-Sergeant is clearly screwed up in the head, Leyton cites staffing issues as the reason for keeping him on the case.

Things aren't going any better amongst the folks of the CPS, with Kate breaking the news to Thorne and Sharpe, and asking the former if he "feels even the slightest bit responsible" for the death in custody. He tells her the only people he feels responsible for are the families  of Tyler's victims. As if on cue, the news shows an interview with the husband of one of the victims, who boldly declares that he's glad Tyler is dead. Clearly, there's no shortage of possible killers in this episode.

Ronnie is surprised to hear the medical examiner tell him that Tyler was asphyxiated, but not by himself - "textbook staged suicide," she declares. This sends him back to look at the security camera footage, which plainly shows Sam approaching Tyler's cell before he was found dead. Leyton gives Ronnie the 'you have got to be kidding me' look.

He hauls Sam and a pair of lawyers into the interrogation room. Sam claims that he was just there to get some paperwork done, and didn't know that Ronnie already had the forms needed. Ronnie watches from the observation room as Leyton goes on the attack, and Sam gets defensive. "Am I under arrest?" he asks, and when he's told he isn't yet, he storms out of the interview, hot under the collar.

In the hallway, he explodes at a pursuing Leyton, saying that he hasn't slept in months due to nightmares he's had since the young crash victim died in his arms. He admits that he went down there "to make [Tyler] feel that pain," but couldn't go through with it, "because being a police officer came first." Though he swears he didn't do anything, Leyton suspends him anyway.

Ronnie follows Sam out of the building, trying to talk to him, wanting to know what he did for the ten minutes he wasn't on the security cameras. Completely wrecked, Sam admits that "I just sat down by that cell door, and I cried like a baby." Though Ronnie tries to reassure him that he's still a good cop, Sam doesn't believe him.

His partner returns to the cells and asks a few more questions of the security guard there, wanting to know how long Tyler was in his cell before his body was found. He's told approximately an hour, but he points out they've only seen 45 minutes of camera footage. So what was going on for the other fifteen minutes?