Silent Witness season 25 episode 5 – What happened to Sam Ryan?

Sam Ryan is currently missing (but alive – more on that later). She was last spotted on CCTV following journalist Oliver Meehan, who was found dead on the ground outside his flat.

He was investigating Unitas Health's funding following a conversation with Tom Faulkner – did the money Sam and her husband Jomo Mashaba acquire to build their business come from corrupt regimes? – and allegations of DNA manipulation.

Jomo's son David, who was one day destined to take up the company mantle, was concerned about Unitas's reputation following the death of health secretary Alice Reynolds and wanted to shield the company from any further scandal.

He visited Oliver at his flat in the hope of persuading him to keep quiet, but their conversation quickly became heated. Oliver struck David, with David responding by punching Oliver, who fell to the ground. David thought that he had killed the journalist, who was alive, if unresponsive, in that moment.

In a blind panic, David then chucked Oliver over the balcony to make it look like he had jumped, which did, of course, kill him.

David's wife Fiona was also embroiled in the series of unfortunate events. She works in stem cell research and used her cutting edge technology to fabricate evidence against Tom Faulkner, although she initially had no idea what her work was being used for.

Before the Unitas launch, David approached his wife and asked her to engineer blood and skin samples. It was supposed to be a one-time request to showcase to their investors what her technology could do. If Fiona refused, the funding for her research would have been pulled.

When the couple learned that Tom had been framed for crimes he hadn't committed, multiple people had already been killed, which left them unwilling to speak up, unsurprisingly. But eventually, the charges against Tom were dropped and he was released after Nikki discovered the genetic barcode in one of his blood samples.

But that very nearly didn't happen.

An intruder managed to gain access to the Lyell using Jack's missing pass. Once inside, they deleted key files and stole important documents and, crucially, the blood samples. Fortunately, one of Tom's samples arrived in the post, addressed to Nikki, which she was able to test and find the evidence she had been desperately searching for.

That sample was sent from Sam, which means she's alive and kicking – although we still don't know her whereabouts, or who attacked her and trashed her apartment.

When she initially swiped the sample from the lab while Nikki's back was turned, all signs pointed to her being a villain, but it now appears that Sam was attempting to help Tom, contrary to his belief.

It should also be noted that before Sam disappeared, she was avoiding her husband, suggesting all is not well within their relationship.

Has Jomo done something unforgivable? Is Sam unable to trust him and if so, why?

There's also a big question mark hanging over Ethan Daley, the brain behind the Vigil Network, a computer programme used by the authorities to identify prime suspects. With Unitas losing investors following the health secretary's death and increased scrutiny regarding its finances, Ethan's backing would have helped the business get back on track given his government connections and influence in the Asian markets

"You need me," he said to Jomo. But that working relationship has ground to a halt, with both Jomo and Ethan weighed down by problems at home.

When Ethan pulled into his driveway following a conversation with Jomo, he stumbled upon a chaotic scene in which his wife was being carted out of the house in a bodybag and his wayward son was cuffed in the back of a police car.

Are the people responsible for all of the other deaths also behind this tragedy? Is Ethan being punished for not toeing the line, with his son framed as Tom was?

And there was yet more catastrophe in the final moments of the episode. David and Fiona had been given protection in exchange for key information that would lead the police to the puppet master or masters pulling the strings. They were being driven to a safe location, with DS Martine Chalal accompanying them. She was on the phone to Nikki, poised to reveal information about Ethan's son, when a lorry caused the car to crash.

It's not clear if there are any survivors but if they are dead, more critical leads have once again been lost.

Silent Witness season 25 finale airs on Tuesday 7th June at 9pm on BBC One. Check out what else is on with our TV Guide, or visit our Drama hub for all the latest news and features.

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