Inside Man continued with its second instalment on Tuesday night and viewers think they've worked out which character could be the key to bringing the storylines together.
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In the latest episode, journalist Beth Davenport (Lydia West) took a trip across the Atlantic to pay a visit to death row prisoner Jefferson Grieff (Stanley Tucci).
WATCH: Are you enjoying the drama?
Meanwhile, vicar Harry Watling (David Tennant) continued his efforts to prove his son's innocence to maths tutor Janice Fife (Dolly Wells), who is locked in his basement.
However, fans think that Janice might not be all that she seems after she told the vicar's wife that she could help the couple get away with her murder, with some suggesting that she could be at the centre of the mystery.
Taking to Twitter, one fan wrote: "Janice is not quite the calm, boring, plain maths tutor she would have the world believe, is she?" while another added: "Nope…something's up with her #InsideMan."
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A third viewer suggested that Janice is plotting to expose the vicar for "some great past crime" while another suggested that she could be connected to Grieff in some way: "I think she is connected to Grieff in the prison. Thus why he didn't want to mention Janice's name ever again."
Fans think Janice is the key to the mystery
Another fan suggested that Janice might even turn out to be the one who kills, writing: "It would be fascinating if she ended up being the murderer: if she managed to kill the vicar's wife and/or maybe the vicar. She seems unusually composed and manipulative for someone in her position."
For those who have yet to watch the drama, it follows the lives of a prisoner on death row, a vicar, a journalist and a maths teacher, all of whom are mysteriously interlinked.
Lydia West plays journalist Beth
The official synopsis reads: "In the US, a prisoner on death row (Stanley Tucci) is seeking atonement as he faces execution. On a train in England, a journalist (Lydia West) is looking for a story.
"In a quiet little village, a vicar (David Tennant) is picking up his son’s maths tutor (Dolly Wells) from the station. All four are about to be entangled in a dilemma that could lead one of them to murder..."
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