Alan Ayckbourn’s Haunting Julia starts innocently enough. A dead student’s attic apartment, converted into a shrine to her memory, is visited by the boyfriend, now married to someone else, who fell in love with her in a lecture hall.

Julia, from Otley, West Yorkshire, was a child prodigy, a musician known as Little Miss Mozart, who died twelve years ago. Was it suicide? Was it murder? Was her talent too much to live with, too much to share with those closest to her?

This may not be among the best of Ayckbourn’s plays – it premiered in Scarborough in 1994, was revived there in 1999 and arrives in Hammersmith in a production first seen last year at the Garrick Theatre, Lichfield – but it’s certainly one of his oddest.

There’s a very long Ibsenite exposition in which the boyfriend, Andy (Dominic Hecht), is apprised by Julia’s father, Joe (Christopher Timothy), an industrial entrepreneur, of Julia’s plight and mystery, before they are joined by a psychic mortuary attendant, Ken (Richard O’Callaghan), who was the janitor in the basement.

Andrew Hall’s production seems over-extended – the original played at just ninety minutes with no interval – and the surprise of a bricked-up wall beyond the central door is not much of a half-time cliff-hanger. The entr’acte music of “If You Were the Only Girl in the World” more appropriately sums up the mood among the three men.

The acting on the wide Riverside stage, however, keeps the tension ticking over. We hear ripples of spooky laughter and snatches of music as a sense of impending catastrophe invades the room; it’s icy cold on this side of the museum display. The lights wobble, the room shakes, something nasty happens under the bedclothes… It’s a strange, obsessive play, but curiously unsatisfactory. The effects seem gratuitous, and the conclusion perfunctory. But Ayckbourn grapples with a burden of responsibility for a young life, and the feelings of guilt and helplessness induced by an impossible, incomprehensible, artistic talent.