So did The Man Who Never Was, which took its title from a 1956 Fox film and a novel that served as the movie's source material, but went no further.
American intelligence agent Peter Murphy (Robert Lansing) is in Germany (couldn't tell if it was East or West) on assignment, and is ready to head home. However, he is pursued by an enemy agent, who kills Murphy's wife. On the run and exhausted, Murphy staggers into a bar, where he finds an exact double, businessman Mark Wainwright (Lansing again), who exits the bar a few minutes later, and is killed by the enemy agent.
From that point, Murphy becomes Wainwright, and his mission has become even more dangerous. Unfortunately, the show's title might've been a bit unwieldy for viewers, who could easily get into Mission: Impossible, which launched the same year on CBS, or The Man From U.N.C.L.E., in its 3rd year on NBC, or even the spy satire, Get Smart (2nd year on NBC). Factor in another WWII spy series also on ABC, Blue Light, and, well, I think you get the idea.
Following is the series opener, which sets the story up rather nicely.
As you all know, Lansing would be given another pilot, but Gene Roddenberry's Assignment: Earth went no further than a backdoor pilot on Star Trek, and it'd be a while before Lansing landed another series gig.