"Laura's not sure if she's a nice person, ultimately, and whether she deserves to have a nice life, or deserves to have children, for various reasons," said Jo Joyner of her character.
"Deep down, she lacks a lot of self-esteem and doubts herself. She doesn't feel like good fun at all. She's forgotten who she is."
Not only does Emily lend a hand with the childcare, which is particularly useful when Laura's husband Rob is absent, she's also someone to laugh with, vent to and confide in over a bottle of wine, which she's been sorely lacking for a long time.
But their new-found friendship is a scheme orchestrated by Emily to, well, we don't yet know what she's planning.
Yet her drastic measures, which have so far involved planting a knife in Eliza's schoolbag and spiking Laura and Tom's drinks during a work social, indicate that she's on a mission to bring Laura to her knees.
Towards the end of the first episode, Emily's motivations begin to take shape when a shoebox filled with newspaper clippings and miscellaneous objects is uncovered from beneath Laura's bed.
The articles reveal that a boy called Jamie drowned while visiting popular holiday destination Brae Point Cove a number of years ago. Stormy conditions were mentioned, but there's far more to this story than a case of bad weather.
Laura and Emily experience visceral reactions to the box's contents. Laura suffers a flashback in which someone – possibly Jamie, or possibly herself – is submerged in water before she hastily replaces the lid and hurries out of the room to compose herself.
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Emily, who takes her time sifting through the articles while alone, is brought to tears by what looks to be a piece of jewellery.
It's a rare moment of vulnerability for Emily and further illustrates that her fury is fuelled by grief.
It's unclear what the connection is between the two women, and also their links to Jamie, but another of Laura's flashbacks suggests that she might have been present when he died.
As for Emily, she has been working with a journalist to shine a light on the truth, hence the phone call she makes at the beginning of the episode, but what is driving her? Is she related to Jamie, which was a reveal employed in previous Channel 5 thriller The Catch, and why does she blame Laura for his death?
And, most disconcertingly, what lengths will she go to in order to expose Laura's secret?
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