S5E23: The One in Vegas

Chandler decides the only way to mend his friendship with Joey is to fly out to Vegas and visit him. Phoebe is determined not to be left out on another adventure, so everyone winds up going. Trouble is in the water, however, when Chandler finds out that Monica had lunch with Richard. Meanwhile, Ross and Rachel try to embarrass each other after an awkward encounter. Chandler and Monica reconcile and hastily decide to get married. Ross and Rachel get drunk and roam the casino. Phoebe deals with a 'lurker' on the slot machines.