Imposter

Brian Aldiss Presents: Imposter. Philip K Dick's paranoid tale is read by Peter Marinker.

"Spence Olham is confronted by a colleague and accused of being an android impostor designed to sabotage Earth’s defences. The impostor’s ship was damaged and has crashed just outside the city. The android is supposed to detonate a planet destroying bomb on the utterance of a deadly code phrase. Olham must escape and prove his innocence, providing he is actually Spence Olham.

First published in Astounding Science Fiction June 1953 issue. 

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