Pic already stars Colin Firth and Taron Egerton with Vaughn directing.
Story follows a veteran secret agent who takes a young upstart under his wing.
Vaughn had always intended to have a big star as his main antagonist, having already pursued Tom Cruise and Leonardo DiCaprio.
With Jackson now in place, Vaughn’s last job is to find the female lead. As Variety first reported Vaughn has shown interest in Emma Watson and “Dark Shadows” actress Bella Heathcote, but no decision has been made yet.
Jackson is repped by ICM Partners and Anonymous Content and can be seen next in Spike Lee’s “Oldboy” remake followed by MGM’s “Robocop” and “Captain America: Winter Soldier.”