Dennis Potter’s plays are well-known for their controversial topics and idiosyncratic style, and this dark and disturbing tale is no different.

Set in a suburban house in the 1970s Mr and Mrs Bates care unhappily for their bed-bound daughter Pattie, left severely disabled by a car accident two years earlier. A chance encounter brings a young man, Martin, into their home – though his claims to be a friend and one-time suitor of their daughter are not all they seem.

If things weren’t fractious enough, the play weaves in religion, racism, and rape – a combination which left the play unscreened for a decade after being originally commissioned for television by the BBC.

Perhaps the most challenging role is Pattie – Sabrina Poole spends most of the play in bed, making only uncomfortable twitches and incomprehensible noises; this is handled sensitively, convincingly, and without melodrama.

As Martin, Jonathan Massey should be the engine of the piece and while he definitely has mercurial charm his delivery would benefit from more hellfire and less contemplation. Stewart Thompson (Mr Bates) is sturdy but lacks a deeper, inner tension, while Abbe Swain plays his wife with a gullible innocence that makes her emotional seduction quite believable.

The Sewell Barn Company is to be applauded for its wide ranging programme and rejection of slavishly commercial scheduling, but it’s hard to see much more than shock value in this particular piece. At its end, redemption is far from both the characters and the audience.