Deep Crimson 1997

Set in 1949 in the northern Mexican state of Sonora and based on the infamous Lonely Hearts murder case, a story which revolves around the unlikely couple formed by Nicolas Estrella, a studied balding gigolo, and Coral Fabre, an overweight nurse, who join forces to exploit old and lonely widows and spinsters. But their plans go awry as Coral can't stand to watch her lover in the arms of other women and starts murdering the intended victims in fits of jealousy.