"Straight Outta Compton," a biopic about the pioneering rap group N.W.A., wowed Hollywood by taking first place in the North American box office in its debut weekend.

Racing past its rivals, and past even the most optimistic of expectations, the film took in an impressive $60.2 million, box office tracker Exhibitor Relations reported Monday.

Yet the movie, which opened in the United States on August 14, comes off as strikingly contemporary as the nation grapples with a slew of recent deaths of African Americans in custody of law enforcement.

It was named after the 1988 debut studio album from the group that gave birth to the gangsta rap genre and launched the careers of Ice Cube and Dr Dre.

"Fuck Tha Police," N.W.A.'s heads-held-high cry of defiance against the Los Angeles Police Department, so alarmed authorities that it generated a warning letter from the FBI, and the song remains a controversial anthem in many protests.

Directed by Gary Gray, best known for his music videos, "Straight Outta Compton" traces the roots of the then teenagers' rage against mostly white police in their gang-ridden home of Compton and other parts of the Los Angeles area.

"What a welcome surprise and the last blockbuster blast of the season," Exhibitor Relations box office analyst Jeff Bock told AFP.

"$60 million for an R-rated biopic featuring an ensemble of unknown African Americans -- as far as I know, that's never happened before, so it's quite rare."

Until the film opened in theaters, Universal Pictures had expected just $20 million in weekend ticket sales.

The studio got a major coup in more than doubling its reported budget of $29 million.

- Largely African American public -

Relatively unknown actors -- O'Shea Jackson Jr (Ice Cube's son, who plays his father), Corey Hawkins and Jason Mitchell -- interpret the roles of the founding members of N.W.A., which stands for Niggaz Wit Attitudes.

Bock says biopics rarely generate such success.

"But a couple of factors went into this opening: one, there hasn't been any studio films that cater to the African-American crowd this summer and two, this was a seminal story in music history that was long overdue," he added.

"Any time you have a group of underdogs taking down the establishment... is always a good place to start for film success.

"This had it all, and said it very poignantly."

N.W.A.'s story is also that over different fates, from American success stories like Ice Cube, a recognized producer and musician to Suge Knight, facing life in prison for a fatal hit-and-run.

The film comes out a year after the death of unarmed teenager Michael Brown, killed in Ferguson last year by a white policeman.

Los Angeles is also commemorating the 50th anniversary of the Watts riots against police violence.

- Rivals trail behind -

The feature sailed ahead of the number two film, "Mission: Impossible -- Rogue Nation," which took in $17.2 million, despite playing in nearly 1,000 more theaters than "Compton."

The Tom Cruise action-thriller, the fifth installment in the blockbuster franchise, has earned a total of $138.3 million in three weeks in theaters.

The other major debut of the week -- "The Man from U.N.C.L.E.," a reboot of the hit 1960s spy series -- earned $13.4 million for third place.

Following in fourth was one of the major flops of the summer -- the comic book action film reboot "Fantastic Four," which took in just $8.2 million in its second week.

Psychological thriller "The Gift" starring Jason Bateman and Rebecca Hall was in fifth place at $6.5 million.

In sixth place was Marvel action flick "Ant-Man" with $5.5 million in its fifth week. Its total earnings now stand at $157.5 million.

Seventh was the raunchy comedy reboot "Vacation," about a family holiday gone awry that stars Ed Helms, Christina Applegate and Chevy Chase, with $5.2 million.

Eighth place went to animated comedy sequel "Minions," featuring the yellow mischief-making creatures, with $5.1 million. Its total haul after six weeks in theaters is $312.9 million.

The ninth spot went to "Ricki and the Flash," starring Oscar-winning actress Meryl Streep as a rock-and-roller trying to mend ties with her long-suffering family, with $4.6 million.

Rounding out the top 10 was Amy Schumer and Judd Apatow's comedy-romance "Trainwreck" with $3.8 million in its fifth week in theaters.