After a terrible accident, a shy homebody of a young woman, Laurel (Zoe Kazan: Ruby Sparks), is mistaken for her identical twin sister, Audrey (also Kazan), and while the mistake is honest at first, Laurel decides to jump on this opportunity to escape the smallness of her life — which mostly involves caring for her father (John Carroll Lynch: Paul) and a wrong-in-so-many-ways “romance” with a teen boy she used to babysit (Sterling Beaumon: Astro Boy) — and take over Audrey’s supposedly glamorous and exciting life in Los Angeles. Kazan is charming in a grounded, authentic way, and her sudden new relationship with Audrey’s tenant and neighbor, Basel (Jake Johnson: 21 Jump Street) — who believes she is Audrey, of course — is sweet and funny, the deception involved aside. But it’s all far too blithe and cheery, yet nowhere near madcap and comic enough, for a conceit embodying such potential latent power: The Pretty One finds an unsweet spot of tonal mismatch. Writer-director Jenée LaMarque, making her feature debut, stumbles across some could-be intriguing issues, such as the dangerous ability to get a fresh perspective on how others see you, but she never capitalizes on them. The plot is far too wrapped up in hoary romantic-comedy shenanigans — also involving Audrey’s married boyfriend (Ron Livingston: Parkland) — and, alas, it’s all too obvious from the very first moments how they are going to shake out. Still, LaMarque has a sure hand as a director. I’ll look forward to seeing what she comes up with next.