This and Star Wars ripped each other off. *some spoilers*

Certainly Message from Space has tons of straight Star Wars rips, but this went both ways as the Star Wars franchise continued.

Return of the Jedi rips Message from Space for the 2nd Death Star destruction. In Message from Space the nut-wielding rebels fly inside the main baddie base to fire on its reactor core center.
Also the climactic one on one duel took place as the simultaneous space battle wages outside the windows and while a shriveled old authority figure cackles in a seated position and watches the action.
Instead of the old woman though, the evil warrior leader ends up defeated and falling through a hole in the floor only to explode at the end of his fall. Just like the Emperor.

There were also a couple other things I noticed which made me think Lucas watched this, but I don't remember them now.


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