Here we see a short-lived ABC television series from 1966-67 starring Robert Lansing. The plot had him as an international spy on the run from enemy agents. Miraculously, he runs into a man who is his exact double. The agents kill that man by mistake, and the real spy decides to "become" him. AS it happens, he was an abusive, alcoholic schnook so everyone from the guy's own wife (who catches the replacement immediately) on down are kind of happy he's "changed"
Lansing was perfect for this role. Never a great actor but a great TV star, he had already played authority figures in leading roles in 87TH PRECINCT, 12 O'CLOCK HIGH, and he would go on to play Gary Seven in the much loved but unsold backdoor pilot on STAR TREK, "Assignment Earth."
BUT...he wasn't the original star of THE MAN WHO NEVER WAS. That was, in the first pilot, Canadian actor Don Harron. While the handsome, robust Harron certainly looked the part, apparently someone at the network balked at toplining a Canadian actor with little US experience at that time. Thus, Lansing took over for the brief run.
Don Harron didn't do too badly for himself, though, as just a few years later, he appeared for the first time as Charlie Farquharson, a role that would make him quite famous in the United States over that country-corn series' long and successful run on network, in first run syndication, and in perpetual reruns! Of course, I doubt most Americans could pick out the REAL Don Harron in a crowd! :P