As if the double-act relationship weren't complicated enough, along comes Toby – real-life sisters Sarah and Lizzie Daykin – with their show Lucky to add a delicious new layer of sibling resentment. The conceit is that stagestruck egotist Sarah has coerced her submissive younger sister into putting on a show. Sarah is brash and brittle; Lizzie is tolerating this public humiliation out of concern for her damaged big sis. It's played with twisted authenticity by the Daykins, so that Sarah's self-promotional sketch show barely conceals a rich and real tangle of desperation, debasement and love.
From the get-go, the imbalance extends far beyond the usual straight-one/funny-one dynamic. Glamorous Sarah hogs the stage, electrified by the audience's attention. Mumbling, near-mute Lizzie shies from the limelight – and when she strays into it, Sarah soon wrests it back. This, you see, is Sarah's big moment, her chance to be "the name on everybody's lips", to vindicate the praise lavished on her by her mum and dad – videoclips of which she shows us. She has us play along to her childhood games. She performs her self-penned Puberty Rag. And she dominates every weird, dark sketch: one about an old lady abusing her cats; another about a married couple whose mutual hatred is revealed by his impatience with her selection of main course ("Have the steak, Diane").
We don't need a shrink to tell us that these skits hint at Sarah's psychic pain. And it's no big surprise when Lizzie emerges, albeit fleetingly, as the duo's real talent, but – at least until the blow-out finale – most of this is suggested rather than shown, and brilliantly so. The carping/sotto voce asides/backchat between scenes, Lizzie's lowered eyes and defeated body language, and Sarah's brattish precocity all add detail to a richly drawn relationship.
The finale plunges further into the abyss, and amusingly implicates the audience in the sisters' plight. Toby's conflation of truth and fiction, the darkness of their humour – and the on-screen contributions from the sisters' parents – echo Kim Noble's recent multimedia docu-comedy about his own depression. But in this show's mining of the full tragicomic potential of female sibling rivalry, it also brings with it the thrill of encountering something new.
