This summer’s box office has found its gravy in action sequels. Following on the heels of the “Alien Versus Predator” success story, the sci-fi sequel “Resident Evil: Apocalypse” opened at number one, generating $23.7 million in sales and kicking the martial arts movie “Hero” out of the top slot.

The Kim Basinger thriller “Cellular” was far behind in second with $10.6 million despite positive reviews. The goofball comedy 'Without a Paddle' slipped to third place with $4.6 million in its fourth weekend.

“Resident Evil: Apocalypse” is the sequel to the 2002 movie based on the video game. Milla Jovovich plays a leader of rebels in a world inhabited by zombies, genetic mutations and evil corporations. Its audience was mainly young men. “Cellular,” the story of a kidnapped housewife who manages to contact a complete stranger on his cell phone, cost about $25 million to make.

Overall sales were down from a year ago. This is traditionally a quiet time at the cinema with the bigger films slated for later in the fall. Next weekend’s fare “Sky Captain and the World of Tomorrow,” “Wimbledon” and the Bernie Mac pic “Mr. 3000” may generate some box office heat.

After 14 weeks in limited release, the indie comedy “Napoleon Dynamite” made its way into the top ten, tying the Tom Cruise movie “Collateral” at number eight with $2.7 million. The movie has been a sleeper hit for Fox Searchlight pictures.