UFO 4: Double Double Toil and Trouble is one long single gen story written by Dale E. Jones. Although gen, it does contain some adult concepts (no slash).
Ed Straker is kidnapped and replaced by an alien double. Faced with the disbelief of his SHADO colleagues, it is up to Straker's body guard to find out what has happened to the real Ed Straker, before Straker is killed by his kidnappers.
"What happens now - to the real Ed Straker, I mean?" Phil asked. "Are you going to brainwash him, amnesia him like you said and let him go? He can't be much of a threat to you now."
"Don't be insane," said the alien, sitting down. "You vastly underestimate him if you think he'll give up. He'll have to die - here and now!"
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