1950 was a hot year for Bradbury; The Martian Chronicles became renowned, granting him prestige he'd previously lacked. Radio loved Bradbury and they adapted "Mars Is Heaven!" twice that year on different network programs: Escape (listen to it at archive.org here) and Dimension X (at archive.org here). The two versions are rather different, with Escape being very faithful. Both tell the story of a human expedition to Mars which discovers a homey U.S. town (from Illinois because it's Bradbury) transplanted to Mars and all the beloved dead ones of the crew residing there. In the climax, the ship's captain realizes the "loved ones" are actually Martians in human form.
Although I normally like adaptations to be as close to the original text as possible, the Dimension X adaptation adds something which I rather like; a new character is added to the crew - a physician who had survived the Dachau concentration camp. A lonely and traumatized man who can no longer recall his family, he finds no one on Mars waiting for him amongst the "dead" - and thus he comes to the realization of what the people truly are.
In other adaptations, such as the 1953 EC comic by Al Feldstein & Wally Wood, the captain comes to the conclusion of the Martians' identity on his own, which renders it something of a solliloquy. The revelation of the Martians' identity is followed by a macabre scene in which the Martians bury the dead humans, which EC and the Escape version kept.
However, the 1989 Ray Bradbury Theater version ends at the moment of the captain realizing what the Martians are. That program had a distinct problem with depicting action - so many episodes would climax at the very moment of the twist, rather than playing any of it out (namely, the death of the captain).
Show up tomorrow for another look at Ray Bradbury!