I love this film. It's a great combination of glamor and action, even if the plot is outrageously convoluted and hard to follow. After a man in Acapulco dies, an insurance company hires Jake Decker (Grodin) to investigate. He enlists the help of a model named Ellie to pose as his wife as they go under cover among the chic, monied ex-pat set. He also calls on a friend (Art Carney), another investigator living down there for information and assistance. The investigation leads them into a hornets nest of organized crime, exiled Nazis and a very lusty Joan Collins. Farrah Fawcett changes clothes every five minutes, to great effect and Charles Grodin and Art Carney nimbly handle the comedy. There's a wonderfully choreographed car chase toward the end that finds Farrah tearing around a bull ring in a yellow Datsun hatchback. All this is set to a soundtrack of great 70's top 40 hits from the likes of Wings and 10cc.
It's difficult to find this film. The trailer is above, uploaded to YouTube by Surfstyley4. It's not available commercially on DVD, at least not domestically, though there is a Japanese release out. This was released on VHS and a few are available on Amazon. I discovered it on TV years ago, but haven't seen it on lately. I did, however, find a reliable source for it on iOffer.com. The poster above is available at MoviePosterShop.com.
Obscurity factor: 8 (available on VHS, but not on DVD, rarely screened on TV, not on YouTube)