Nightsleeper viewers have a surprise theory about THIS character

Nightsleeper, the new BBC train drama that's gripped the nation, continued tonight on BBCOne - and viewers have a surprising theory about this character.

The six-part thriller Nightsleeper, written by BAFTA-winning writer Nick Leather, released its latest episode tonight (Sunday, September 29th), and the latest scenes have prompted viewers to question one character's motives in particular. 

'Is Abby fooling us all and is really the villain here?' asked one viewer on X (formerly Twitter). 

While another asked, 'What if a big twist has Abby as the perp?'

And another said previously, 'Omg is Abby in on this???'

While another had previously speculated, 'Are they trying to silence Abby? Getting too close to the truth? Yes, I am invested now.'

Meanwhile other fans had a different theory, with another commenting, 'Yep. The guy who took over from Abby is definitely the hacker. He knew the train was going to speed up when trying to slow it down.'

While another said, 'I really do not trust this Paul guy, Abby's mentor.....he is giving off pissed off overlooked old geezer but "saviour" complex vibes.'

And another fan of the BBC train drama said, 'See I'm the only one noticing the Abby Joe, Joe Abby thing.'

The new BBC series has had mixed reviews, with some viewers questioning how realistic the plot is.

'OMG! Has anyone watched ‘Nightsleeper’?' wrote one fan on the social media platform X.

'It’s inadvertently hilarious Think ‘Acorn Antiques’ does an amateur dramatics version of ‘Speed’ - but on a train, with a cast of characters straight out of ‘Little Britain’ Watching at a friend’s & we’re sore from laughing.'

While another said about the show, 'I really wished they screened #Nightsleeper within a week. Most ppl watched ahead to the end because it was gripping (and silly) and it would have had much bigger impact.'

Nightsleeper continues next Sunday on BBCOne. You can catch the whole series on iPlayer now.