I remember nearly everything about this person with the exception of his name. He saved dozens of lives and would work through the night in the heat of combat, yet it turned out he learned everything on the fly and was just a man who kept leaping from alias to alias. Anyone know? Anyone know of anyone similar?
If you have your wars mixed up you may be referring to Ferdinand Demara a U.S. citizen who served during the Korean War on a Canadian naval vessel, the Cayuga, as a surgeon under the name Dr Joseph Cyr one of a number of aliases. A book about him, The Great Imposter, by Robert Crichton was published in 1959 and also distributed by Readers Digest. There was a movie of the book starring Tony Curtis in 1961. Your description reads a lot like my memory of both the book and the movie.