The V&A museum, London dug up some early Searle history. His sketch of a prisoner production of 'Hamlet' with the artist appearing as the ghost! Link here
The prisoners would stage plays and comedy revue shows to buoy their spirits. Searle drew programmes- only one or two copies each- that were disseminated around thousands of hands.
'General Collapse' (Lilliput). Artist: Ronald Searle (signed). Media/Technique: Pen (fountain pen) and ink (black carbon ink) on good quality artists paper attached to board. Artist's signature at bottom right. Coloured ink showing measurements. Graphite notations on top right. Damage to tall man’s face. The fibres are disturbed or lifted. Other media/information: Verso Reference written in waxy black media. Coloured ink (red) stamp showing return address of artist. This is crossed out and new return address is written by Searle. This reads 32 Newton road W2, Bay 3942. Drawings for magazines Ministry of information. Original artwork for Mirror, Echo, Blick in die welt. (Mirror & Echo).
More on Searle's wartime experience here