At Swim, Two Boys, The Place, London <!-- none onestar twostar fourstar fivestar -->

The water is gorgeous. In Jamie O'Neill's award-winning novel At Swim, Two Boys, the heroes' relationship develops in and by the sea. This physical theatre adaptation, by Wales-based company Earthfall, takes place in a square, very shallow pool that takes up the whole stage. There are sheets of reflections under the dancers' feet, water lights glinting on the walls.

Directors Jim Ennis and Jessica Cohen also have to deal with events on shore. The boys' love affair develops during Ireland's 1916 Easter Rising, with the threat of ending up in opposing armies. Newsreel footage, mixed with new film, is projected on to the back wall of Gerald Tyler's set. Taped voicesunderline key incidents.

The adaptation never looks streamlined. I haven't read the novel, but I'd guess that Earthfall couldn't bear to cut anything. More clips imply that fighting has started. There's little sense of plot and history moving forward. Events do not unfold.

We never feel the two contemporary dancers, Terry Michael and Stuart Bowden, belong to the world of the newsreels, making it hard to see cause and effect. And they are not teenagers. They're fearless in the slipping, soaking dances, but they don't suggest adolescence's changeability.

The choreography, credited to The Company, sticks to a basic vocabulary. The two men's dancing evokes a relationship, but lacks the depth and variety to show its development. Rather than gradual change, we see many similar incidents.

The most eloquent movement comes at the start. The beautiful set has a high wall behind the pool, a barrier with vertical markings and a swimming-pool ladder. Bowden enters the water, leaving Michael gazing, unsure whether to follow. Then they lie down, each body echoing the other with understated yearning.

Roger Mills's music keeps things moving forwards and changes the mood. He and Frank Naughton play several instruments, mixed with taped drumbeats and contemporary songs.

Though the production is diffuse, Earthfall creates some fine images. When the men lift each other, water drips into the pool, marking the floor patterns in splashes and ripples. They dive and slide across the floor, sending up plumes of water. I began to fear for the electrics, the musicians and their instruments, but Tyler's golden lighting makes every drop shimmer.