Director Stephen Kijak is prepping a movie-length documentary for theatrical release on one of the biggest boy bands of all time, Backstreet Boys, for U.K. and US production banner Pulse Films.

Kijak, whose résumé boasts the docs Stones in Exile and Scott Walker: 30th Century Man, will detail the group's tumultuous journey from child stars to full-grown boy band.

Produced by Mia Bays and Thomas Benski and exec produced by Lucas Ochoa, the music documentary is billed as a tell-all project about all five original members of the band -- A.J. McLean,Howie Dorough, Nick Carter, Kevin Richardson and Brian Littrell -- and aims to be finished by the fall.

Backstreet Boys sold in excess of 130 million albums worldwide, putting them among the top 30 best-selling global artists of all time.

"What drew me to this project is the band's openness and willingness to push themselves into uncomfortable places, to be vulnerable and honest and to be really trusting of the filmmaking team to steer them in the right direction," Kijak said.

He promised the film wouldn't just be some "3D boy band puff piece," adding that, "BSB is getting real, and it has been exciting to work with them as they explore their past and start to look towards their futures."

Kijak described himself as a fan of them "as people first and foremost," noting that his way into the subject matter was the human story behind the music and success.

"We always wanted to make a film, and now is the ideal time," the group members said in a statement. "With Kevin back, the fact that we are masters of our own destiny, a new album in the works and our 20th anniversary -- it all adds up to being the right time to share our story."

The band continues to have a huge following in territories worldwide including Japan, Latin America, Germany, U.K., the U.S, Canada, China, India, Spain and Mexico. The group's recent concerts still deliver big audience numbers all over the world. An album and world tour are also in the works.

Director Kijak brought his Scott Walker picture to Berlin in 2007 and his Stones documentary unspooled at Cannes in 2010.

In 2012, Pulse produced and released Sundance hit Shut Up and Play the Hits, charting the final days of cult U.S. band LCD Soundsystem.

The banner also co-produced the Katy Perry/Paramount film Part of Me 3D andNo Distance Left to Run, about seminal U.K. band Blur by director duo thirtytwo.