It follows Monk, a brilliant detective with obsessive-compulsive disorder. He returns to solve one last case involving his stepdaughter Molly, a journalist preparing for her wedding.

More than a dozen Angelenos navigate Valentine's Day from early morning until midnight. Three couples awake together, but each relationship will sputter. A grade-school boy wants flowers for his first true love. Two high school seniors plan first-time sex at noon. A TV sports reporter gets the assignment to find romance in LA. A star quarterback contemplates his future. Two strangers meet on a plane. Grandparents, together for years, face a crisis. An 'I Hate Valentine's Day' dinner beckons the lonely and the lied to.

Mia Thermopolis has just found out that she is the heir apparent to the throne of Genovia. With her friends Lilly and Michael Moscovitz in tow, she tries to navigate through the rest of her sixteenth year.