This used to turn up fairly often on TV, either in the afternoon "Million Dollar Movie"-type slots, or late at night on weekends. I think it was probably distributed in the US by American-International Pictures; it seems like it was in the same syndication package as Godzilla vs. the Thing, The Amazing Colossal Man, I Was a Teenage Werewolf, etc. The "robots" were actually humans who were brainwashed/hypnotized by a mad scientist (Rey) and sent out to commit assassinations. Constantine played a Bond/Flint/Solo-type secret agent hero who, naturally, was assigned to stop the villain. I saw it when I was 12 or 13. The main thing I remember thinking at the time was that Sophie Hardy (as the heroine) was cute, and that Francoise Brion (as the villainess) was hot. If I understand correctly, the original European title translates as "Cards On the Table." Maybe the European producers wanted to appeal to "Casino Royale" fans, and AIP tried to appeal to "Ultra Man" fans. It's a lot more spy-fi than sci-fi.It seems to have been released in B&W, although I've heard that a color print was shown in Spain.