Gene Barry plays the central character of the movie, Dr. Clayton Forrester, a scientist from Cal Tech. He and two buddies are fishing nearby when the initial Martian invasion ship lands (crashes) nearby. By the way, that must have been a heckuva landing the Martians had to endure when their 'meteors' touched down.
The movie details humanity's efforts to halt the apparently unstoppable murderous Martian invasion force. No pretenses about peaceful coexistence or some sort of misunderstanding here, folks. The Martians want our planet and are willing to kill every man, woman, and child on it to get it. As such, the military is portrayed in a pretty good light in this film (unlike many others). After all, when the alien's first club out of the bag is lethal force, then you pretty much have to go with the flow.
In the end, with atomic weapons having failed to stop the invaders, mankind appears doomed. Saving the day, however, is the most unlikely of allies (and, no, I ain't talking Russia).
Overall, a well-paced sci-fi/thriller with a basic premise that never fails to entertain when it is well done--as it is here.