Checkout Agather Christy Murder in 3 acts. Vdub heaven!

Do you mean Murder In Three Acts by Agatha Christie? It was a screen adaptation of her 1934 book 'Three Act Tragedy.'

The motion picture version was made in 1986, starring Peter Ustinov and Tony Curtis:

http://www.imdb.com/title/tt0091572/ 

I assume it's the 1986 movie version that has the VWs in it? There are scenes set in Acapulco, Mexico. There was also a TV episode version in 2010 starring David Suchet as Poirot.

you two sound like David and Margaret
M

More Leonard Maltin I hope