Duncan Sullivan is the ex-husband of Phoebe Buffay. He is portrayed by Steve Zahn. He was a Canadian ice skater who married Phoebe to get a green card.
Duncan Sullivan was a good friend of Phoebe Buffay. Duncan was thought to be gay and he was on a green card and he was nearly deported. Phoebe agreed to secretly marry him so he could become a USA citizen. Phoebe fell in love with Duncan, but he traveled the country because he was an ice dancer. Phoebe was heartbroken when he left. ("The One With Phoebe's Husband")
Six years after getting married, Duncan returns to New York to ask Phoebe for a divorce because he realised he's not gay and wants to marry a woman he was in love with. Phoebe is heartbroken that he wants a divorce but she agrees to let him divorce her. Phoebe and Duncan part ways on good terms. ("The One With Phoebe's Husband")