The director of musical comedy Pitch Perfect 3 has explained why three of the series' most prominent male characters do not appear in the sequel.

Bumper Allen (Adam Devine), Benji Applebaum (Ben Platt) and Jesse Swanson (Skylar Astin) - boyfriends of members of the Barden Bellas - are all absent from the third film in the franchise.

Trish Sie, who also directed Step Up: All In as well as many of the videos for alternative rock band OK Go, said the scriptwriters cut the characters before she was signed on, and pointed out that Platt was busy on Broadway.

“I think the main purpose was these girls are moving on with their life," she told the Hollywood Reporter. "Maybe they’ll get back to these guys at some point. A lot of people don’t end up with their college boyfriend.

“We wanted it to be about them and their independence and finding their way in the world and moving ahead alone," she added. "And it just felt like it was time to make a fresh start.”

Sie also said she hoped the Pitch Perfect franchise, which stars Anna Kendrick and Rebel Wilson, could continue with more sequels in the future.

“I would see these movies on and on and on until they start sucking," she joked. "I think whether it’s these women in the next stage of life or it’s a new group of women going through these things, I think there are endless ways to chart the course of the girls’ lives and a woman’s life.

“If you were to do a reboot you’d have to spend a lot of time making the chemistry right. But assuming you can get that — singing, dancing, laughing, solving problems together, unlikely heroes, band of misfits — that stuff is sort of timeless and wonderful and, as far as I am concerned, I would watch it over and over and over again.”