The love-struck zombies of ‘‘Warm Bodies’’ swarmed the box office on Super Bowl weekend with a $20 million opening. On a weekend that Hollywood largely punts to football, the PG-13 film from Lionsgate’s Summit Entertainment easily led the box office, according to studio estimates Sunday. The Super Bowl always means a significant slide in movie-going on Sunday — studios predict a decrease of as much as 70 percent from Saturday to Sunday — but ‘‘Warm Bodies’’ still lured many teenage fans. The film is about a zombie whose love for a human redeems him. The film appealed particularly to females, who made up 60 percent of the audience. Action films continued to fare poorly in 2013, as Sylvester Stallone’s ‘‘Bullet to the Head’’ opened with just $4.5 million for Warner Bros. That meant his brawny cohort Arnold Schwarzenegger bested him when his ‘‘The Last Stand’’ opened with $7.2 million in January. But both openings were poor. Along with the weak performance of Jason Statham’s ‘‘Parker,’’ which has taken in $12.4 million in two weeks for FilmDistrict, moviegoers aren’t turning out for traditional R-rated action movies. Last week’s top film, Paramount’s ‘‘Hansel and Gretel: Witch Hunters,’’ dropped to second with $9.2 million on the weekend.

Ocean won’t seek charges