Ally Darling has had 20 boyfriends, and makes the mistake of reading a women's magazine article that says that a woman who has had more than 20 lovers has a harder time ultimately marrying. Ally then wonders if one of her "magic 20" might have been The One, and sets about tracking them all down....just to check. What’s your number is a frothy version of frothy romantic comedies, I think you know what I mean.