Cheat on ITV episode 1 review and recap: did Leah or Rose kill Adam?

So what do we know so far? And what questions do we have? Here are five talking points from that explosive first episode...

1. Adam is dead – but did Leah kill him? Or was it Rose?

"You are still not convinced that we got the right one, are you?" DI Bould (Justine Mitchell) asks DI Hammond (Jimmy Akingbola) as he stands staring at the evidence board.

"They both look so innocent," he replies, examining two photographs: one of Leah Dale (Katherine Kelly), and one of Rose Vaughan (Molly Windsor).

In the mortuary lies the body of Adam (Tom Goodman-Hill) with a puncture wound in his chest.

Cheat's Tom Goodman-Hill: playing an adulterer is "cathartic"

But which of these two women killed him – his wife Leah, or her student Rose? And has the "right one" actually been brought to justice for the crime?

The truth about what happened has yet to unfold, but as the drama cuts between a prison visiting room and long flashbacks to the events that led us there, there are tantalising hints of what's to come.

In the present day, Leah and Rose sit either side of the glass in an austere room in prison – but it's not clear who is visiting who. And when Leah says she wants to talk about Adam, Rose asks: "You don't miss him, do you?"

She adds: "It's okay, you can't help how you feel. It's amazing how quickly you can adjust to life without someone if you never loved them in the first place... tell me Leah, do you feel guilty?"

2. Adam and Leah's marriage is in crisis

Rewind right back to the beginning of the story, and we find Leah and her husband Adam in a troubled relationship that has hit a particularly rough patch.

Adam desperately wants a baby, but so far – despite his rigid and stressful baby-making sessions – there has been no joy. Then, when fertility tests reveal that he is actually the one shooting blanks, he reacts by cruelly throwing it back in Leah's face: "It's worked out nicely for you, hasn't it? You never even wanted kids in the first place." Ouch.

It's probably a good thing they haven't brought kids into this relationship yet, because there are a LOT of issues – and most of them are coming from Adam.

Meet the cast of Cheat

Despite apologising for lashing out, he's clearly so obsessed with getting Leah pregnant that he cannot see beyond his own desire for a child. He snaps at Leah when she retrieves her bottle of dosatriptyline from the bathroom cabinet (labelled "avoid in pregnancy"), most likely a variety of amitriptyline – that is, an antidepressant or pain medication.

If she's back on meds, what does this mean for their plans to have a baby, he asks? What does she want?

"To sleep, I just want to sleep," Leah says, to his irritation. Despite that ominous remark, not once does he ask if her mental health is okay, or why she feels the need to restart medication.

A fellow professor at St Helen's College, he is also wildly unsupportive of his wife and constantly dismisses her concerns, questioning her judgement and her perception of reality, and accusing her of always being paranoid. You could even call it gaslighting.

And to act like she is the one being unreasonable when he invited Rose in for a drink and a late-night heart-to-heart at their home! The cheek. "For what it's worth she's a nice girl, she's very smart," he says, but he might as well have said: "I don't believe you".

3. Rose has the upper hand over Leah

Molly Windsor and Katherine Kelly in Cheat

At this point, Rose is running rings around her professor. The student is clearly a master at emotional manipulation – and everything Leah does just makes things worse for herself.

We saw that in Rose and Leah's meeting with the woman from academic affairs. Suddenly Rose was a sobbing, sympathetic wreck, tearfully telling Leah, "I've always felt that you have something against me." The professor came across as vindictive, and the student as a victim.

Rose was also the one who heard Leah masturbating in the bathroom, a fact she twists to suggest that the plagiarism allegation is a form of retaliation. And then she manages to rile Leah even more by writing on the bathroom stall: "Leah Dale was here – frigging herself off."

While Rose has perfected the art of winding Leah up by making her look unhinged, Leah isn't so great at hitting back: her stunt in the lecture hall – when she tricks Rose into claiming someone else's words are her own – looks unprofessional and nasty. Rose: 1, Leah: 0.

4. Adam has fallen for Rose's charms

Molly Windsor and Tom Goodman-Hill in Cheat

Rose is clearly determined to wage war against Leah, and she seems to have decided to use Adam as part of her strategy. When she turns up at the house late one night, claiming she needs to drop off essay notes and asking for a glass of whisky, every element of the visit is designed to pique his interest.

Although she pretends to admire Leah, Rose makes clear that she is most impressed by Adam. He is so smart! And clever! And modest! And such a good teacher!

Unfortunately, Leah's husband seems to be falling for Rose's charms, which is not hugely surprising given their relationship problems right now.

5. Rose (probably) killed Betsy the cat

Although Adam makes out that Leah is mad to claim that Rose stole her cat Betsy, killed her and dumped her lifeless body outside the house, Rose is looking pretty guilty right now.

After turning up uninvited at the house, Rose legs it while Adam is out of the room, carrying a large bag in front of her. Later, love-struck college porter Ben (Burn Gorman) whispers to her in the library: "You know that other thing you asked for? If you're really sure, I'll sort it for you."

We suspect that he may be referring to the killing and/or dumping of the poor kitty, who is later discovered dead and missing a collar. "Poor Betsy," Rose says when Leah brings up her cat's untimely death – and she doesn't sound too sincere.

Cheat continues on Tuesday 12th March at 9pm on ITV