Superstar Kat Valdez is a well-known figure in the Latin community who has had four failed
high-profile marriages. After "Marry Me", a song by Kat and her fiancé, Bastian, becomes a chart-topper across the world, they plan to hold their wedding ceremony in front of a streaming audience at one of Kat's concerts. Charlie Gilbert, a divorced math teacher, is guilt-tripped into attending the concert with his friend Parker and his daughter Lou, who has lately been less than enthused with him. Just as Kat prepares to go to the altar, a showbiz gossip website publishes a video of Bastian's
infidelity with her assistant Tyra. Kat's manager shows her his phone, revealing the fast-spreading news to her. Without any distress, Kat sees Charlie in the crowd holding Parker's sign reading "Marry Me"; to the surprise of the entire venue, she impulsively decides to do so. Unsure, Charlie goes onstage and marries Kat in front of the world. After the ceremony, she refuses to speak with Bastian or Tyra as she and Charlie leave. The two are awkward and polite to each other before Kat goes home with a broken heart. The following day, needing to respond to the frenzied media coverage and speculation about her mental state, Kat decides to stay married to Charlie for a few months to put a positive spin on the situation. He reluctantly agrees, not wanting to cause a stir in either of their personal lives. Charlie poses for media appearances, though he is uncomfortable with the scrutiny. They eventually begin to grow close after spending time together away from the media and her management. Charlie eventually asks Kat to a school dance as a date, and she accepts: that night they kiss and sleep together for the first time, spending the next few weeks together in a real romantic relationship. Kat also ingratiates herself with Charlie's students and Lou: while Charlie prepares his math team for a mathalon with Kat's encouragement to the students. Kat works especially with Lou, who has stage fright, teaching her to dance to take her mind off her anxiety. Bastian shows up to announce that "Marry Me" has been nominated for a
Grammy, Kat's first nomination. Charlie is wary of the fact that Kat and Bastian will have to perform together again, but she insists it is over between them. However, Charlie becomes unsure that he can compare to Bastian and fit into Kat's world: reasoning that their marriage was never real to begin with, he breaks up with her. Kat writes a love song, "On My Way", that becomes more successful than "Marry Me". While filming an appearance on
The Tonight Show with Bastian, Kat realizes it is the night before the mathalon, where she promised to support Lou and Charlie. She corrects rumors, stating that she and Bastian are not back together and she did not write "On My Way" for Bastian but for Charlie, she then abruptly departs the show. Rushing to reunite with Charlie, who is helping Lou overcome her stage fright with the dance Kat taught her. Kat holds up a sign asking Charlie to marry her again, to which Charlie agrees. Kat, Charlie, and Lou become a happy family with their dog. In the credits, a series of couples and their stories of how they met are shown. ==Cast==