Haldene tracks down a man named Cochrane, who turns out to be a killer from the future.
The one calling himself Cochrane is not of this era, but of a time far forward.

Variants

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  1. “Retroflex” by F. M. Busby, in Vertex, October 1974.
  2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . written by F. M. Busby