Is faith a kind of madness? And why do we choose to believe what we do? Robin French’s new drama, set in Victorian England, has fun with life’s absurdities, but beneath the whimsy lie serious and substantial questions about the nature of existence.

Marking Darwin’s bicentenary and the 150th anniversary of On the Origin of Species, the piece has a fantastical flavour of Victoriana. Looped red velvet curtains and painted cloths are raised to reveal the home of Lucius Trickett (Ronan Vibert), renowned taxidermist, widower and father to a bright-eyed, sharp-minded teenager, Lucille (Kate Burdette), who is a wheelchair-user. The room is crowded with a stuffed, glass-eyed menagerie: a swordfish hangs from the ceiling, and there are antelopes, bears, a giraffe and all manner of outlandish creatures, brought to a crude and motionless simulacrum of life by Trickett’s hand.

Trickett himself is so helplessly grief-stricken over the loss of his beloved wife that his associates fear for his sanity. He is also much exercised by the rise of what he sees as godless Darwinian theory, though his outrage is not entirely the product of devout piety. His stubborn insistence on an afterlife hinges on his need to believe that he will ultimately be reunited with his wife.

So when he hears of the adventurer Gilbert Shirley, dispatched by the bereaved Queen Victoria on a quest to track down an elusive, perhaps even mythical, creature called the ghost loris — a primate whose suicidal tendencies seem to fly in the face of Darwin’s ideas — he becomes obsessed with preserving it and showing it to the world, thereby discrediting Darwin and defeating notions that for him spell unendurable despair.

Acts of creation — human and divine — are juxtaposed, and the work itself, with its intersecting fictions, plays narrative games with our expectations, even if we can see it unravelling long before French untangles the stories’ strands. The whole needs tightening and the characters could be better defined.

But the biggest problem is Robert Wolstenholme’s production, which, despite solid acting and quirky, detailed design by Christopher Hone, is painfully slow and static. French’s writing has an eccentricity that is often appealing, but occasionally self-consciously arch: it needs a quicksilver directorial touch, and Wolstenholme’s is leaden. This is a clever play; but it demands far more vitalising energy.

Box office: 0844 4771000, to Nov 29

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