Warning from Space

Uchûjin Tôkyô ni arawaru is a movie starring Keizô Kawasaki, Toyomi Karita, and Bin Yagisawa. UFOs are seen around Tokyo. Because they look like giant starfish the aliens cannot approach us without creating panic. Hence one of them...
Large star-shaped aliens travel to earth in hopes of warning them about an oncoming catastrophe. To prevent panic about their appearance, one alien takes the form of a popular singer.