Who is Theo?

Amidst the late-night din of St. Patrick's Day in New York City Donna comes home to find a highly intoxicated man named Theo who is dressed like a leprechaun in her apartment. Mistaking Theo for her roommate Jamie's sublet Donna puts him into the empty room only to learn that Jamie is still home. With no explanation of how he got in Donna and her roommates try to figure out where Theo came from and how to get him out of the apartment. Theo's undeniable charm and seemingly magical habits ho