Goke, Body Snatcher From Hell (1968) review

A massive yellow UFO (in a crimson sky) causes a plane to crash - while on land, one of the passengers (who, by the way, is an assassin) gets way too close to the alien craft and what appears to be angry grape jelly seeps into his head and makes him hunt the other passengers (who are very busy bickering with each other).  It's a cheap and schlocky horror movie from Shochiku - The Blob from 1958 must have been an influence - with a feeble anti-war message (one of the passengers, coincidentally an American widow, was on her way to get her husband's body who was killed in Vietnam) and several unintentionally funny reaction shots of females screaming.  Best if viewed when under the influence of multiple substances (my suggestion: candy corn and pumpkin ale) so you can safely ignore the continuity errors and appreciate the downbeat ending, in which the aliens finally decide we're inept at being civilized and take over.