Grey's Anatomy," but she also has more than a few great romantic comedies under her belt. These are her seven most memorable, ranked.
7. 'New Year's Eve' (2011)
To be honest, we forgot Heigl was even in this movie, but maybe that's for the best because it's just so bad. She plays a chef who, at one point, makes out with Jon Bon Jovi, which is either a positive or a negative depending on your feelings. It's your life (sorry, not sorry).
6. 'The Big Wedding' (2013)
Woof, what a movie. Diane Keaton is at her most Keaton in this movie, and it's just too much. The very thought of this movie gives us a headache. Heigl isn't even part of the main romantic pairings, so her character, by default, becomes the least insufferable out of the bunch.
5. 'Killers' (2010)
We don't quite understand how anyone thought making this movie was a good idea, but here we are. "Happy Endings" star and all-around hilarious comedienne Casey Wilson saves it from being a real stinker.
4. 'The Ugly Truth' (2009)
Yes, both of these characters are the absolute worst, but it kind of works, right? We're not saying you should watch this movie every weekend, but as far as rom-coms go, you could do worse.
3. 'Life as We Know It' (2010)
While we'll never forgive this movie for killing off Christina Hendricks in the first 10 minutes, it's pretty cute. Heigl and Josh Duhamel have some great chemistry, and we can actually laugh with the movie instead of at it.
2. '27 Dresses' (2008)
You can't hate something with James Marsden in it -- you just can't! Plus, it helps us remember that Heigl can be funny when she picks the right material.
1. 'Knocked Up' (2007)
Could anything else be No. 1 on this list? "Knocked Up" is funny with or without Heigl, and it was the 2007 Judd Apatow comedy that made us want to see more of her outside of "Grey's Anatomy." While her post-"Grey's" work hasn't exactly met our expectations over the years, we'll always have "Knocked Up." And no one can take that away from us.