When this 30 something year old, Ally Darling (played by Anna Faris) begins trying to become serious in her life, she starts to count down the number of relationships she had in her life. All these were precipitated by her reading a magazine article that women who had more than 20 relationships would have a hard time finding a husband thereafter. She counted that she had 19 already but then again, she finds her ex-boss naked on her bed with her. That's number 20 and she doesn't want to marry him so she decides to go back to her ex's and somehow she might hook up with one of them so she won't go way past 20.
The rest of the movie is a journey with her ex's with the help of her neighbor, Collin Shea (played by Chris Evans). She employs him to track down her other ex's so she can reach out to them, what happens next is a comedy joy ride for most these ex's.
In the end, Collin and Ally hook up one evening but she would not have it the next since, she found out that Collin tracked down one of her ex's and did not inform her. She was disappointed at him and he was sad that she was still going after one of her ex's right after the two just hooked up.
It turned out that this ex was keeper in Jake Adams (played by Dave Annable) and they hit if off nice and well until she realized that she wasn't comfortable with Jake. She wanted to be herself and wants someone to accept her for who she is, and she thinks Jake wasn't it. She misses Collin and went to various wedding events to look for him. When she did finally meet him, she confesses her love for him and he became her number 21.
In the last scene, a call came in for Ally and it was her ex-boss. As the call went straight to an answering machine, both Ally and Collin overhears the message that she and her ex-boss did not "do it" so Collin is number 20. This made Ally very happy as she did not go over the proverbial number 20.
Currently being shown in Amazon Prime Video at the time of this being written.
