No Strings Attached overhauled last week's number one film The Green Hornet in a close battle to the top of the weekend's box office charts. The Natalie Portman/Ashton Kutcher led romcom took a comfortable lead on its opening night, was narrowly out-grossed by The Green Hornet on Saturday, but then turned the tables with a close Sunday win. Overall the Ivan Reitman film triumphed with a $20.3 million victory over The Green Hornet's $18.1 million haul. As No Strings was made for around $35 million when all is said and done, they'll be happy enough with this at Paramount but perhaps they will rue the missed opportunity of mostly being unopposed by any other new releases. Still the r-rated sex comedy didn't do The Dilemma numbers. The film's $20 million opening was fairly typical for an Ashton Kutcher film and practically identical to the initial weekend takings of What Happens in Vegas which went on to make $80 million domestically. The latter film managed to keep making money mostly thanks to its opportunistic release which saw it competing with a number of male-targeted blockbusters such as Iron Man and Indiana Jones. No Strings Attached has seen 70% of its opening weekend attended by females which I guess means that the other thirty percent were disgruntled male dates/partners/critics? The film has also been also been released at an opportune time with testosterone fuelled Jason Statham vehicle The Mechanic unlikely to attract a large female audience during its run this weekend. The following week however No Strings Attached will likely have trouble against two new releases starring females in prominent roles; psychological thriller The Room-Mate and underwater action drama Sanctum 3-D. Has it made enough to sweeten Sony on Ivan Retiman directing Ghostbusters 3? That'll be the wider implication here. Box Office Mojo report that The Green Hornet has already out-grossed previous superhero comedy Kick-Ass although this is a relatively small success given that Kick-Ass featured little star quality, played on less theatres and was developed on only a quarter of the Green Hornet's reported 125 million budget. The Seth Rogen vehicle has grossed 63 million in 10 days and should comfortably stide past the 100 million mark domestically with the films worldwide box office receipts ensuring that it becomes a minor hit.