Silent Witness's latest set of episodes were a heartbreaking story that touched on the reality of the mental health system, both now and in the past, with the death of two characters the team had to investigate. But who killed Arthur and Ryan?
The first episode in 'Creekwood: Part One' aired last night, following a slight change in schedule, and saw Nikki, Jack and the rest of the team investigate the murder of an unidentified man, who was found with a screwdriver impaled in his eye.
Their search led them to two couples sleeping rough, a food bank and a burgled house. But what did all this have in common? Well all paths lead to Creekwood, a former mental health institution, that they believed Arthur may have been a patient at. Except that's not exactly what happened, here's how the rest of the story played out and crucially who murdered Ryan and Arthur.
Silent Witness episode 4 ending explained
Who killed Arthur?
Arthur's death kicked off episode three after he was discovered with a screwdriver impaled in his eye.
After a lot of investigations, the team discovered Arthur Lane changed his name from Henry Dankford to Arthur Lane many years ago. They found out he was now working at helping the homeless with drug addiction and providing them with medication they needed.
However, they then found out he had been a surgeon at Creekwood Hospital and had carried out lobotomy procedures on patients, which involves a similar procedure to how Arthur was found dead with the screwdriver in his eye.
After some digging Nikki discovered Henry/Arthur had assisted on many lobotomies but only carried out one himself - which was on a child known as Child A. After his surgery on Child A he stopped his work and changed careers. Thanks to Harriet's connections they were able to discover Child A was actually Tommo who worked at the food bank with Vincent.
The team split up and head to Tommo's flat which he shares with Vincent, where they discover the pair have a joint bank account that gets £1,000 from Arthur Lane each month. They also discover a missing screwdriver and temazepam, aka the murder weapons, causing DI Moss to arrest Vincent in connection with the murders.
Meanwhile Arthur Lane's daughter discovers her father has left half his estate to Tommo, which Tommo doesn't want and the pair get into an argument, with Tommo pulling a knife out on her. Tommo goes onto say Vincent is his only friend and he protects him, and that it was Vincent who said Ryan would hurt Tommo. He also reveals Vincent told Tommo that he needed to help Arthur, just how Arthur had "helped" him aka by giving him a lobotomy.
It becomes clear Tommo wasn't aware of what he was doing and that it was in fact Vincent pulling the strings, including getting the £1,000 a month payment and half of Arthur's estate, and so while Tommo technically did the killings he wasn't really responsible for them.
Who killed Ryan?
The second episode opened up with Erin discovering Ryan was dead on top of a car park, seemingly having committed suicide after falling back into a drug addiction. However, Erin was convinced that Ryan was clean and insisted to the police and Nikki the only drugs Ryan was taking were prescribed drugs for his bipolar disorder. So who gave him the drugs? Well that would be Arthur Lane, aka the man who was found dead in episode one.
It turns out he was a former medical professional who was helping those who didn't have fixed addresses get access to medical treatment and drugs. Erin also told the team Ryan met Arthur at the food bank, where Arthur volunteered.
Following an autopsy and forensic evidence it appeared Ryan hadn't injected himself with heroin but was likely dosed by someone else before his death. After doing a toxicology report the team found out Ryan had been injected with temazepam, which just like Arthur had been, would make him more pliable and easy to manage, before being killed.
The team discovered the paint used by Vincent at the food bank was discovered on Ryan's body, however Vincent claimed he was busy when Ryan was killed. They then suspected it was Danny who had killed the pair of them because of what his mum went through at Creekwood, however he had an alibi of working at the pizza shop.
It was then discovered that it was actually Vincent and Tommo at the food bank, although it was Vincent pulling the strings and telling Tommo to do the murders.
Silent Witness continues next week on BBC One and BBC iPlayer
