Episode 11 of "Ally McBeal"
s01e11 Silver Bells

Three intelligent, successful and motivated adults approach Judge Whipper Cone about the possibility of getting legal representation in their quest to have the courts approve a legal, binding, three-way marriage. Fish assigns Ally and Cage to the case, knowing Ally's incurable romanticism and Cage's legal acumen is a potent combination with Whipper assigned to the case. Ally is opposed, claiming the three-way relationship is morally repugnant, but Georgia, feeling punkish around the holidays, points out that the clients' triangle isn't very different from the one in which Ally, Georgia, and Billy find themselves. Georgia accuses Billy of being more relaxed and open in their marriage ever since Ally re-entered the picture. Whipper, herself experiencing an annual bout of Holiday Blues, causes Fish to propose marriage, even though both know he really doesn't want to.