'Humans' returns for its second series on Sunday.

Based on the hit Swedish series Real Humans, series one of this collaboration between Channel 4 and AMC in the US had the sheen of a big budget about it, lifting it above your average British TV drama. The plot, meanwhile, was so well-written, and it wore the science part of its so sci-fi lightly, that those that might normally run a mile from a show about robots threatening the very existence of the human race weren’t alienated.

The first series threw up plenty of questions, from the moral – is it strictly cheating if your wife’s out for the evening and you decide to engage ‘adult mode’ and have sex with your synth – to the downright existential: what is consciousness, or indeed, what is it to be human?

That last one’s rather a biggie, so for the purposes of this blog, we’ll set about some more immediate, easier-to-answer posers asked at the end of Humans‘ first series. And before you ask, you can’t just find a way of watching the second series of Real Humans, which aired in 2013, to find out. The two series have a slightly different plot and different ending. Sure, the Scandi version would be entertaining viewing, but wouldn’t tell you anything about our Leo, Mia, Niska and friends. One final thing, this blog features spoilers, so if you’re still catching up on Series 1 (it’s available to stream on All 4), look away now.

Where is Niska going?

The final scene of the first series saw Niska on a train, hard drive in hand containing Elster’s code for synth consciousness. Where is she going? Scotland? And what is she going to do with it? She learned so much as the series went on – namely how to play with toys thanks to Sophie. But there’s a ruthless, hard killer buried deep in her root code, and after her treatment in the synth brothel, we can hardly blame her for being suspicious of humans. She’s essentially famous, too, given she was plastered all over the news for her antics at the smash club. No wonder she’s seen in the trailer for S2 wearing a wig. That same trailer also features reports of other synths waking up – has Niska shared that code already? Or are they waking up of their own accord? Did she delete the version on the drive she handed to Laura, or are their two copies of the code? There’s every chance Niska will actually be the villain of the series, which would put the rest of Elster’s children in an interesting dilemma. Writer Sam Vincent has hinted it may happen, but was suitably vague on the details.

How are the Hawkins family going to feature?

Channel 4’s synopsis for the series states: “As unconfirmed reports of synths behaving inexplicably surface, the ripple effects of one simple yet seismic decision sees the past return dramatically and surprisingly to the door of the Hawkins house. Joe, Laura and the entire family are faced with a difficult choice that will put the family under an intense spotlight.” This dysfunctional lot were crucial to the synths’ survival in series one, and as they reunited as a family – as Laura mended her relationship with Mattie, forgave Tom and explained the death of her younger brother – the more use they became to their robotic friends. Mattie’s knowledge and Laura’s legal skills are likely going to feature heavily, but what’s in the past that can reappear? Laura’s brother? Her mysterious mum she was visiting as the first series opened? Or maybe one of her cases?

What’s happened to Fred?

He was last seen under a dust cover, having been hacked by Hobb, who wants to give consciousness to all synths, but only so he can enslave them again. Strange guy. Fred, though, is a key member of the synth family. Surely there’s a rescue mission in the offing?

Is David Elster Actually dead?

David Elster is the man who designed the synths and wrote the code to give a select few consciousness. He also created Beatrice – that’s detective Karen Voss – to replace his dead wife. But if he’d cracked the ability to bring life to robots, and bring his son Leo back to life, why did he kill himself? Did he even kill himself, is perhaps a more pertinent question? We’ve never seen a body, his children have never shared memories of it, and in the very first episode, Leo was heard saying to the others “If it’s him, we run”. Given that they didn’t know Hobb had his research unit and army at this point, and there was so much Hobb didn’t know about them, who was it they were running from? Maybe it was Elster and they know he’s alive? Niska alluded to her creator abusing her, so there was definitely a dark side to Elster and more to find out. Might we hear it from the man himself?

Will Pete get over Karen?

DS Pete Drummond hated synths. His wife, her from Strictly, going off with one won’t have helped, but at least he had his colleague Karen to talk to. But wait – she was a synth all along. How she became a police officer is another thing, but where does that leave Phil? Will he even be in the new series? Neil Maskell is widely expected to return, although his name wasn’t on the casting announcement.

Who is Carrie-Anne Moss playing?

Formerly best known as Trinity from The Matrix, more recently, Canadian Carrie-Anne Moss has been bossing it in the Marvel TV universe as lawyer Jeri Hogath in Jessica Jones and Daredevil. This time out, she’s playing Dr Athena Morrow, a pre-eminent AI expert, hired by fellow newcomer Milo Khoury, a tech billionaire interested in continuing David Elster’s work. Cast member Tom Goodman-Hill has hinted they’ll form a “huge” part of the story and writer Vincent has said they’ll form an antagonistic force in the series.

Where did Anita take Sophie?

This may have been dealt with in the first series, or may have been more about setting a sinister mood than an actual plot device, but where did Anita – before she returned to being Mia – take Sophie that night? It felt as if it was related to Leo’s drowning, but was never cleared up. Perhaps in this series it will be. Not long to wait.

Humans returns to Channel 4 on Sunday October 30, 9pm.