Ok, this is low-budget cheese with bad acting and awful special effects, but it is such a wonderful example of the dubbed for US kids movies that came out in the 60s.
You should be willing to forgive the movie testing your patience with a seemingly endless flashbacks featuring fight scenes from other Gamera films such as Gamera (1965) and Gamera vs. Gaos (1967). These scenes, which serve no purpose except to cut costs by using existing footage and padding the running time, certainly drag the movie down. Luckily we are soon back to the aliens who are invading the Earth because they need the nitrogen in our air (did we mention that?).
Destroy All Planets will make you shout at the screen which is always the hallmark of an enjoyable bad movie night . . . Besides any movie with the line “Gamera, destroy Tokyo!” can’t be all bad now, can it?
Nachos and beer recommended.