Original post here. This image was researched by Bacchus at ErosBlog as part of the “Γ commission.” The research was originally published at Hedonix as “Γ 032 – Aliens Need Teen Girls. Here is what Bacchus found.

This is a poster for Night Caller From Outer Space, a movie which (according to Wikipedia) was also released as The Night Caller and Blood Beast From Outer Space. This 1965 British movie is based on the novel The Night Callers by Frank Crisp. The plot features aliens from Ganymede who kidnap teen Earth girls for breeding purposes. There’s a detailed and sympathetic review of the movie here that offers comparative information on the different available DVD versions. Horrorpedia offers additional information, and another review here offers this view of the magazine the aliens placed bogus modeling ads in to lure the girls to their alien breeding doom:

Here’s a larger view of the similar artwork on the poster for the “Blood Beast” version, at least one of which is available for sale: