Silent Witness star Amanda Burton reprised her role as Professor Sam Ryan in a dramatic instalment on Monday night (23rd May) after 18 years off screen.
After the season 24 finale saw Sam calling upon her successor Nikki Alexander (Emilia Fox) to ask for her help, fans were left hoping for a dramatic return – and that’s exactly what they got last night.
Season 25 kicked off with a bang as Sam's husband (Hugh Quarshie) was injured in an intense shooting that killed the health secretary.
However, as Sam summoned the team with a plea to help investigate, Nikki was sceptical about her intentions and questioned whether she was trustworthy.
Sure enough, Burton has hinted there could be ulterior motives from the Lyell’s original pathologist.
Talking to Metro.co.uk, she hinted that a darker side to her character could be set to emerge.
"Is Sam really telling the truth?" she said. "Who is she working for? It’s very intriguing because she’s always been so much on the right side and has always had such integrity for the truth and all the rest of it.
"Now, we’re sort of seeing that she could be a bit of a double-edged sword," she explained.
Her co-star Fox added: "It’s awkward, because they have mutual respect for each other, and are curious about each other... We want to trust Sam, but there is definitely something going on."
Jack Hodgson star David Caves also previously addressed Sam's "ambiguous" return.
"She comes back and it's not immediately obvious what her motives are, whether she's trustworthy," he told RadioTimes.com. "Again, that's coming at it from a slightly different angle.
"You would have thought, 'Oh she's definitely one of the good guys.' But a lot has happened to that character in the 17 years she's been away, so she's not going to be the same person entirely."
Caves went on to say that, with Sam's entrance "ambiguous", the rest of the team aren't sure whether she can be trusted or not.
"We're thrust into this world that we're not very familiar with at all. We feel very awkward quite quickly because it involves the UN and Big Pharma, big tech companies, health passports, which is a very topical controversial subject," Caves explained.
"We slightly feel like fish out of water initially when we arrive on the scene. It becomes very clear, very quickly that all is not what it seems and there are other forces at play that will seriously call into question the credibility of DNA and forensic science as a whole."