The notion of identical strangers is a weird cliche that really isn't common at all. But you'd think it happens a lot judging by a lot of old films! In "Lancer Spy", George Sanders plays dual roles in this WWI thriller...a German officer AND a British soldier who looks just like him!
The story begins with the capture of Baron Kurt von Rohback (George Sanders). He's a high official in the German military and his capture is fortuitous since Lt. Michael Bruce (also George Sanders) looks exactly like him! So Bruce is trained and watches von Rohback through a one-way mirror until he knows enough about him to impersonate him. Eventually, Bruce replaces von Rohback and he along with his valet are allowed to escape from British custody. Once back in Germany, he's embraced as a hero and resumes his previous duties...and spies for the British.
To enjoy this film, you really do have to suspend your disbelief and not keep telling yourself how ridiculous the plot is. Of course it is...but is the movie any good in spite of this? Well, yes and no. While George Sanders is a good actor, here he seems out of place. His German accent is pretty bad and you wonder why they didn't find someone who could do both a British and German accent better than he did. It also seemed very odd to have von Rohback's girlfriend played by the Mexican actress Delores del Rio! She is supposed to apparently be Hungarian!! And, what her character did at the end simply made no sense at all!!! On the other hand, the film does have some very good supporting actors and the film is interesting and keeps your attention. Enjoyable AND a bit dumb...what an unusual combination!
By the way, if you do watch this film, get a load of del Rio's costume at the 60 minute mark...it's certainly special!