James Gunn is returning to direct with stars Chris Pratt, Zoe Saldana, David Bautista, Michael Rooker, Karen Gillan, Vin Diesel, Bradley Cooper, Sean Gunn and Glenn Close coming back as well.
Heroic Hollywood first reported the news, saying Flanagan will play one of the Ravagers who have a bounty out on Rocket Raccoon, which causes conflict within the group.
Principal photography began on the film at Pinewood Studios in Atlanta on Wednesday.
Kevin Feige is producing, with Gunn also writing the latest draft. The movie is set to bow on May 5, 2017.
Flanagan was a fan favorite on the hit FX show “Sons of Anarchy” as Chibs, a loyal member of the motorcycle gang. He was recently seen on Fox’s “Gotham” and is currently filming “Sand Castle” alongside Henry Cavill and Nicholas Hoult. Other past credits include “Braveheart” and “Sin City.”
He is repped by Gersh, the Curtis Brown Group and Untitled Entertainment.