Sometimes it's the little things that get you: that's the case with this affecting installation created by the constantly surprising Sound&Fury. Charlie Ward takes you into the pain-addled – and possibly morphine-dulled – mind of a young soldier called Harry, who is being treated in a makeshift hospital behind the front line during the first world war. Such patients were sometimes entertained by Charlie Chaplin movies, projected on to the ward ceiling so that the immobile wounded could watch from their beds. The clownish Chaplin was a mascot for British troops – one regiment even held a cut-out of him above a trench in the hope that the Germans would die laughing.

The piece, for 10 audience members at a time, lying on iron bedsteads, lasts a mere 16 minutes. Like Chaplin himself, it is small, but just so. Even the location is well thought out, taking place in the treasure trove that is the Cinema Museum, which occupies part of the old Lambeth workhouse where a young, destitute Chaplin and his mother were briefly residents.

Here you lie in the darkness and watch a Chaplin movie projected above you. Like Harry, you are aware of movement and noise around you. Gradually, the movie – with its seaside location – and Harry's memories become entwined. The silent, flickering celluloid evokes sounds of a long-ago day on a beach; Harry's father pointing out Halley's Comet to his young son; the fireworks of a family gathering merge into the guns-and-mortar fire of war.

It has a real hallucinatory quality, and offers glancing parallels between the young Harry, so full of promise and growing into manhood, and the celluloid little man, Chaplin. The latter is initially seen as a pratfall prankster, but is eventually glimpsed on the no-man's land of a beach, alone and desolate, like a tragic clown only just beginning to realise that the joke is on him.

• Until August 3. Box office: 020-7840 2200. Venue: Cinema Museum, London