LOS ANGELES — Greek-hero movie “Hercules” may not out-muscle superhuman “Lucy” in the box office this weekend.

“Lucy” is expected to gross $45 million, higher than the $30 million to $35 million projection for “Hercules,” according to people who have seen pre-release audience surveys. Meanwhile, the comedy “And So It Goes,” also opening this weekend, is expected to draw in less than $10 million.

“Dawn of the Planet of the Apes,” the 3-D sequel to the 2011 blockbuster “Rise of the Planet of the Apes,” will likely cede the top spot at the box office after ruling domestic cinemas for two weekends in a row.

“Lucy,” distributed by Universal Pictures, follows a party girl turned unwitting drug mule (Scarlett Johansson) who ingests a powerful chemical that transforms her into a superhuman with enhanced abilities.

The R-rated film, which co-stars Morgan Freeman, generated early buzz. At WonderCon, held in Anaheim, California, in April, the film’s writer and director Luc Besson revved up the crowd when he screened two sequences of “Lucy.”

On Rotten Tomatoes, the film received 63 percent on the “tomatometer” as of Thursday. Fandango, which surveys moviegoers, said in a news release that the female-powered thriller leads the weekend’s ticket sales on the website.

“Hercules,” directed by Brett Ratner and co-produced by Metro-Goldwyn-Mayer Pictures and Paramount Pictures, follows the ancient man and myth (played by Dwayne Johnson) as he leads a band of mercenaries to help end a civil war in the land of Thrace.

“Our movie is for everyone,” Beau Flynn, one of the producers of “Hercules,” told the Times at the film’s premiere on Wednesday. “It’s a huge movie and ‘Lucy’ is R-rated, we’re PG-13. ‘Lucy’ is kind of a late-college-age film, but I think that ‘Lucy’ looks cool.”

With about a $100 million budget, the studios are expecting ‘Hercules’ to bring in about $20 million in its release, which is more conservative than analysts’ projections. On Rotten Tomatoes, as of Thursday, the film had 67 percent on the “tomatometer.”

This will be the second Hercules movie to hit the big screen this year: Actor Kellen Lutz played the demigod in “The Legend of Hercules.”