In 1923, 43 revolutionaries were arrested for an abortive uprising in Bulgaria; whilst awaiting execution, they were imprisoned on a small island controlled by a sadistic, militaristic captain. The film details a number of fruitless escapes, eventually culminating in their final, successful flight.

Rangel Valchanov's technical control and the convincing acting overcome a certain stereotyped characterisation to make the film eminently worthwhile. Together with Sun and Shadow, this film indicates that Bulgaria may be a rising film producing country.

On a Small Island received an Award for Direction at the Czechoslovak Festival.