Adam (Kutcher) and Emma (Portman) are two old friends who accidently reunite after years apart. After waking up one morning together, they want to meet again and give their no-strings-attached fling another go. So they agree on a set of rules to maintain the spark between them, without it actually turning into a real relationship with the usual flaws, unnecessary baggage and expectations.

Although they become friends with special benefits, Adam must cope with his growing feelings for Emma and the fact that she insists on being a casual friend and nothing more. Obstacles set down by his best friend (Johnson) and his father (Kline) add further complications to the plot.

Even for such a predictable storyline, No Strings Attached actually has a decent setting and an interesting point of view, since it's traditionally men who seek no-strings-attached affairs; in this case, it’s Emma who calls the shots. In fact, she furiously rejects flowers, gifts, or even the words 'I love you'.

While Kutcher and Portman are both attractive leads, they play their one-dimensional characters blandly save for a few witty one-liners. Johnson is annoyingly unfunny as Eli, Adam's best friend, giving a weak delivery to his lines and joke. It's a mystery why he's cast as Adam's sidekick. Kline is also a huge letdown in the film, playing the hungry-for-sex dad who ends up dating his son's ex-girlfriend, despite the fact that he loves his son so much – a disturbing relationship indeed. Another peculiar casting choice is US rapper Ludacris as Adam's other best friend for further comic relief. Sadly, the jokes are on him.

No Strings Attached seemed initially promising, especially given Portman’s recent Oscar win and reputation as a terrific and versatile actress. The film seriously lacks the humour that its trailer promised and its romantic comedy genre expects.

It is charming in its own way, and somewhat funny in rare moments, but in the end, No Strings Attached is a disappointing R-rated comedy by respected director Ivan Reitman (Ghostbusters, Twins, Six Days Seven Nights). You won't be laughing out loud, but you may not neccessarily hate yourself for paying to see this film.