The Venus' Tear Diamond (1971)
Romantic comedy musical about two jewel thieves who go after the same diamond (under cover of a pan-Asian singing contest) but end up stealing each others' hearts (oh, how tired you'll be of hearing that witty line by the end of the film).
Utterly lightweight with dreadful acting, but proved reasonably entertaining for about an hour... unfortunately at 103 minutes it definitely outstayed its welcome. For supposedly famous professional thieves, the two stars are almost completely useless - a locked drawer almost defeats them completely!
May appeal to fans of lightweight romantic commedy inna 60's stylee, but I think I'll go back to the martial arts films :p