While "To Heinie, with Love" is a pretty good episode, it also relies on a plot device that just isn't logical in the least. If you can look past that, it's worth seeing.
A new navigator joins General Savage's bomber crew. However, the new guy, Lt. Muller (Keir Dullea) is a bit odd...quite and standoffish. But he also has a secret and perhaps this accounts for some of this...his father was a proud member of the American Bund. This was a huge organization of Americans who were pro-Nazi and were pushing for a fascist government in the States.
All this is quite interesting....and then comes a big plot problem. During a mission, a crew member looks inside Muller's wallet and sees a photo of some guy in full Bund uniform!! This is contrived because men were NOT supposed to bring wallets with them on missions AND you'd think Muller would NOT have such a picture on him because it would only make other air corps folks think he was a Nazi sympathizer. He claims later that it was the only photo he had of his beloved father! Huh?!?!
If you can look past this clumsy portion of the film, the rest is very good...particularly how Muller manages to convince everyone he is a true-blue American and a valued crew member.