The funny can be credited to screenwriter Elizabeth Meriwether, who not only creates lead characters that are likeable, but has surrounded these people with a surprisingly rich supporting cast. There is not token best friend that gets all the lines. There's actually a posse. Natalie Portman's Emma and Ashton Kutcher's Adam are surrounded by friends and co-workers that are very very funny without having to resort to outrageous infantile humor. Heck, they all seemed like they could be any of the inherently funny people that I know in the real world.
Adam and Emma meet cute as teenagers at summer camp where his sheepish moves on Emma fall flat. The run into each other again at a frat party in college, then again a few years later. As always happens in the movies, they are destined to end up in the same state, in the same town, at the same time. So when drunk and depressed Adam calls every phone number in his cell for a booty call, he ends up waking up in Emma's Los Angeles flat surrounded by her roommates. Emma is now a workaholic doctor, and Adam works as a middling minion in the television business. Emma doesn't have the time or energy for a real relationship, so she proposes that she and Adam become fuck-buddies. What guy would refuse?
I think it is interesting that there is a string of "no strings attached" sex comedies spilling into the theaters. And they all seemingly have the same twist (which is not much of a twist when they are all the same): In the modern take, it is the guy who falls for the non-committal woman first. But where the similar setup of Love and Other Drugs failed from lack of chemistry between Jake Gyllenhaal and Anne Hathaway, Natalie and Ashton actually make a cute couple. Their quips seem natural, and even though Emma is a bit over-the-top bristly whenever she thinks she is being conned into a relationshippy-type moment, she is still appealing. And who doesn't like to see Natalie Portman have an occasional potty-mouth moment? That's right. We all like a smart girl that swears.
No Strings Attached does falter a bit. It struggles with momentum toward the end as it falls into the predictable territory of whether or not these lovers should also be together for realz. Hollywood does always want the perfect kiss at the end. But until then, I was totally enjoying the ride. Along with great supporting turns by Greta Gerwig, Mindy Kaling, and Lake Bell (along with more awkward appearances by Kevin Kline and Cary Elwes), No Strings Attached is funny escapism with a great cast that won't leave you feeling cheated after your two-hour fling at the movies.