When the air of ambiguity is wafting around Madeleine Girling's dust-sheet covered design, which extends even up to the first floor here, the strangeness of the play is a fiercely compelling force. Disjointed, enigmatic speech refuses to settle into any easy rhythm, Max Pappenheim's soundscape builds an irrefutable creeping sense of horror and as a spiky sibling rivalry comes to a head, taking the unknowing newcomer as a prisoner in its war games, the tension that Mercatali builds is unbearable.
But as it is shattered by the terrible revelations that surely come, there's a slight sense that this is the work of a writer still coming into her talent. Heavy-handed symbolism leaves as dodgy a taste as that fish pie surely does and the way in which the crucial information comes to light - in two long-winded monologues that wrap up the night - feel too much like naked emotional manipulation, determined to make one cry in its tragedy (and succeeding with a fair few) but effectively disconnecting characters from the world of the play.
Paul Rattray's Teddy suffers most here, despite his heartfelt conviction, and it is telling that Paul Hickey's interloper - near-silent at the end - gets one of the more touching emotional moments much earlier in a gorgeous conversational passage about the nature of pain and grief and detachment. Lorna Brown and Yolanda Kettle duel well as the sisters though - both scarred by the past and fuelled by bitterness and guilt to endlessly replay this vicious cycle, leaving us questioning whether the past will ever let go, whether these people can ever move on. A very strong production of a play that just about deserves it.
Running time: 90 minutes (without interval)
Booking until 7th March