The film features a massive ensemble cast including Ashton Kutcher, Julia Roberts, Jamie Foxx, Anne Hathaway, and Taylor Swift. The main plotlines include:

, a temp worker at a talent agency, tries to hide her side job as a phone sex operator from her new boyfriend, Jason (Topher Grace) .

, a florist who proposes to his girlfriend Morley (Jessica Alba) , only to realize he may actually have feelings for his best friend, Julia (Jennifer Garner) .

discovers that the man she is dating, Harrison (Patrick Dempsey) , is actually married.

The story of the 2010 film follows a series of interconnected stories in Los Angeles as various people navigate the highs and lows of love, heartbreak, and new beginnings on February 14th.

An elderly couple, , face a long-hidden secret that threatens their decades-long marriage.

By the end of the day, some relationships crumble, others begin, and many characters find that love often appears in the most unexpected ways.