Series three of Marcella continues on Tuesday night, with another gripping episode starring Anna Friel as troubled detective Marcella Backland going undercover as Keira Devlin to bring down the gangster Maguire family.
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However, viewers couldn't help but notice the introduction of a new character a few episodes back. Matthew, played by actor Glen Wallace, appears to be a figure from Marcella's past who has managed to find her under her new alias.
While he hasn't actually appeared in past series, he has been a regular on TV screens for several years. Get to know the actor here...
WATCH: Are you watching Marcella?
Who does Glen Wallace play in Marcella?
Viewers first met Glen's character Matthew in episode two of Marcella, when he unexpectedly catches Marcella/Keira off guard. As the series progresses, we find out more about Matthew and how he is linked to Marcella's past. Speaking about his character to The Express, he teased: "He is a story from Marcella's background and given the set of circumstances she is in now, being undercover, there becomes an element of jeopardy.
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"Because there are only three people in the whole show who really know who she is. To have someone who may know about her past, that has upped the stakes."
What else has Glen Wallace been in?
The Northern Irish actor has had a number of roles on British soaps over the last few years but is probably best known for portraying Malachy Fisher on Channel 4's Hollyoaks. After three years on the show, which earned him a Best Actor nomination at the British Soap Awards, he left in 2010.
He went on to appear in Doctors, Holby City and Emmerdale before landing a recurring role on Eastenders in 2014, where he played police officer DS Cameron Bryant. Following that, he landed another regular stint in Scottish soap River City before being cast in the CBBC series Jamie Johnson.
Glen is also on screens in Coronation Street at the moment
Last month made his debut in Coronation Street as Carla's scheming ex, Lucas, which is where viewers of Marcella might recognise him from. While he only appeared in a couple of episodes in January, just this week he returned to the cobbles to stir up even more drama.
What are fans saying about Marcella?
Viewers have all had a mixed reaction to the latest series of the Scandi-Noir inspired drama, with many taking to social media to give their verdict. While some have been left confused about the storyline - especially episode five's twist ending - others were seemingly gripped by the plot and have been loving the drama's twists and turns.
Marcella season three has divided viewers
One viewer tweeted: "I don't understand people who say that don't get it this year/can't follow it?? I mean, she went off the rails last series, apparently died, now she's still working undercover to expose a family, the family are corrupt, what's the big deal?"
A second fan said: "Omg that was so good, I love the dramatic music that goes with the scenes in #Marcella I'm so gripped right now. Who is that buried in the pig muck who Marcella took the ring off, so many twists and turns wow!"
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