LOS ANGELES - Cameron Diaz and Ashton Kutcher are in negotiations to star in the romantic comedy "What Happens in Vegas ..."

The story is set in motion following a night of debauchery in Sin City, when two strangers (Diaz and Kutcher) discover they have gotten married and one of them wins a huge jackpot with the other's quarter. In trying to determine the rightful beneficiary of the winnings, the duo embarks on a series of plots to undermine the other, falling in love along the way.

Julian Farino, one of the primary directors of HBO's "Entourage," is directing the 20th Century Fox project.

Kutcher most recently starred in the Coast Guard adventure movie "The Guardian," while Diaz reprises her voice role as Princess Fiona in "Shrek the Third," which opens Friday.