Valentine's Day

It is Valentine's Day and florist Reed Bennett (Ashton Kutcher) proposes to his girlfriend Morley Clarkson (Jessica Alba), who accepts. Reed’s closest friends, Alfonso Rodriguez (George Lopez) and Julia Fitzpatrick (Jennifer Garner), aren't surprised when Morley changes her mind and leaves Reed the same day. On an airplane to Los Angeles, Kate Hazeltine (Julia Roberts), a captain in the U.S. Army on a one-day leave, befriends Holden Wilson (Bradley Cooper). When the plane lands and Kate has to wait hours for the taxi, Holden offers his limousine, which Kate accepts.

Julia, an elementary school teacher, has fallen in love with Dr. Harrison Copeland (Patrick Dempsey), but does not know that he is married to Pamela (Katherine LaNasa). Harrison tells her that he needs to go to San Francisco for a business trip. Wanting to surprise him, Julia also flies to San Francisco, despite Reed's warnings. Julia finds out that he is married and gets the name of the restaurant where he and his wife will be dining that evening. The restaurant's owner allows her to dress as a waitress, and Julia makes a scene at the restaurant, making Pamela suspicious. One of Julia’s students, Edison (Bryce Robinson), orders flowers from Reed, to be sent to his teacher. Julia suggests to Edison to give the flowers to a girl named Rani in his class who has a crush on him.

Edison's babysitter Grace Smart (Emma Roberts) is planning to lose her virginity to her boyfriend Alex Franklin (Carter Jenkins). The planned encounter goes awry when Grace's mother discovers a naked Alex in Grace's room, rehearsing a song he wrote for Grace. Edison’s grandparents, Edgar (Héctor Elizondo) and Estelle Paddington (Shirley MacLaine) are facing the troubles of a long marriage. Estelle admits to Edgar about an affair she had with one of his business partners. Although she is deeply sorry, Edgar is very upset. Grace’s high school friends, Willy Harrington (Taylor Lautner) and Felicia Miller (Taylor Swift), are experiencing the freshness of new love, and have agreed to wait to have sex.