Nightsleeper star responds to shocking Abby revelation in episode 4

The show is airing on Sundays and Mondays on BBC One, but viewers can watch ahead if they wish on BBC iPlayer, where all six episodes are currently available to stream.

Those who have reached episode 4 will know that suspicion falls on the National Cyber Security Centre's Abby Aysgarth (Alexandra Roach) following a shocking break in the investigation.

RadioTimes.com spoke to co-star Gabriel Howell, who plays Abby's colleague and lodger Tobi McKnight, about the latest twist, including how it weighs on Abby's mind and what it says about the wild world of big tech.

Nightsleeper episode 4 reveals that the code used to hack the UK rail network was first created by Abby herself, during her misspent youth as a rogue hacker, which ultimately led to her being brought in by the government organisation.

Howell explained that a key aspect of the character is that she's a "high achiever" and "perfectionist", meaning that she's probably quietly pleased to see her code proven effective in the field.

"She wrote the code which is this prodigy genius s**t, no one else in the world has done it," he said. "She's at the forefront of her field. But then that code is being now used for the exact opposite of what she needed it for.

"And so I think there's probably a little bit of like, 'Oh, it works!' But then I think that school prefect that is in Abby, her stomach would just drop because it's like, 'Yeah, I did it, but it's not me that's testing it. It's actually out there and it's gone'."

Howell went on to draw parallels between the storyline and real-world developments in tech, pointing out that often major advancements are made and released to the world without much thought to the consequences.

"I think there's a lot of stuff like that in cyber… [technology] that was just made and then it gets put out there, and then suddenly it's bigger than we understand. AI, which is going into deep fake, which is going into face scanning," he added.

"I know that there’s stuff that was created for games or apps [initially]... and now they're tracking people on their way home from protests. And it's like, how have we got here?"

Nightsleeper is available to stream on BBC iPlayer.

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