Tom, greeting-card writer and hopeless romantic, is caught completely off-guard when his girlfriend, Summer, suddenly dumps him. He reflects on their 500 days together to try to figure out where their love affair went sour, and in doing so, Tom rediscovers his true passions in life.

Santa Claus and the mischievous brothers Heat Miser and Snow Miser are the targets of yuletide treachery when the North Wind tries to take Santa's place.

Alice, Judy and Sally are three Australian roommates who are unlucky in love. Over the course of a year, they endure numerous personal ups and downs. Meanwhile, Ewan, Joel and Neil are friends and coworkers with similar problems, and gradually their lives intersect with the trio of women to varying degrees. Will any of these young people finally find a satisfying relationship?