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Tweedledum and Tweedledee is a 1967 British novel by Alec Coppel.
The Daily Telegraph said the novel had "some nailbiting moments" and "an ingenious nemesis".
It was written as a movie script. The script was optioned by Charles Matthau in the 1990s who said "Coppel is a master of suspense who can set up 12 plot points in a single scene. All it needs is to be contemporized." However the film was not produced.
Premise
James Farrow, a movie star, hires a lookalike to stand in for him at public appearances. The double turns out to be a killer.
References
Alec Coppel: Australian Playwright and Survivor by Stephen Vagg 2010, Australasian Drama Studies
"The Devil in Manhattan". The Daily Telegraph. 25 May 1967. p. 21.
1967 edition