McClure, as always, excels as Emma, who is someone you want to root for while simultaneously acknowledging that her memory is unreliable. She’s under pressure for a big work promotion and wants to fight the good legal fight while also juggling office politics.

Alongside that, she also has to manage her responsibilities to her husband and children, leaving little room for Emma to catch her breath, all of which is placed under further strain when her long buried trauma rears its head, turning her world on its head. 

As her life begins to unravel, her wits begin to falter and she’s unable to trust anyone, not even herself, even when relying on those around her is what she needs. 

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The supporting cast are also spectacular, offering nuance to characters that could all-too-easily become two-dimensional in a story which revolves around Emma and her struggles. Fowler, who goes toe-to-toe with McClure in several scenes, comfortably matches the lead’s intense energy, delivering a mature performance in her portrayal of a teen who is so defiantly naive. 

Similarly, Cullen’s depiction of Robert as a steadfast-yet-frustrated support source for Emma, even as her behaviour becomes increasingly more erratic, makes their marriage feel authentic. 

Lyndsay Marshal (Inside Man, Hanna: The TV Series) is also another scene-stealer as Caroline, a new friend of Emma’s who is trying to decipher just what exactly is going on.

Insomnia is largely a tale of concealed trauma and how, unless confronted, it will always bubble up to the surface. Emma has lived her life denying her mother’s existence, but when she is no longer able to run away from the truth, she begins to realise that understanding her past is the key to her having any kind of future at all.  

However, as the show continues fundamental elements of the story become lost in muddled subplots and twists, and in turn, Insomnia loses its way. Despite scrambling to tie up its loose ends, key questions are brushed over dismissively and ironically, you’re left feeling more dazed and confused than ever.

This is something that Pinborough’s writing has fallen victim to before, especially in the cross over from novel to screen. Netflix series Behind Her Eyes, also based on one of her novels, had similar problems it couldn’t quite rectify.

Much like Behind Her Eyes, the faults in Insomnia don’t make the ride any less compelling and enjoyable, but it does bring you back down to Earth with a thud as the dissatisfaction sets in.