The 3-D animated feature 'Shrek Forever After' beat out the comedy 'Get Him to the Greek' to finish first at the weekend box office.

'Shrek Forever After' (Paramount/DreamWorks), the fourth and purportedly final installment of the cartoonseries, took in $25.3 million to finish at No. 1, according to early estimates from Hollywood.com. The new Shrek adventure has been atop the box office for three weekends in a row, and has taken in $183 million so far. Final numbers will be available on Monday.

'Get Him to the Greek' (Universal) a comedy starring Jonah Hill and Russell Brand, debuted at No.2 with $17.4 million.

'Killers' (Lionsgate) with Katherine Heigl and Ashton Kutcher, opened at No. 3 with $16.1 million.

Paul Dergarabedian, president of the box-office division of Hollywood.com, said in an email that the domestic box office has been down from last year three weekend in a row. 'The movies currently in the marketplace are simply not engendering enough excitement on the part of audiences the way [a] year ago moviegoers were psyched about films like 'The Hangover' and 'Up',' he says.

Dergarabedian says that the box office may fare batter when 80s flashback movies 'The Karate Kid' and 'The A-Team' open next weekend.