Tatum, 35, is also producing the project along with Reid Carolin, Lauren Shuler Donner and Simon Kinberg.
Script is written by Josh Zetumer, while the "Gambit" character was created in 1990 by Chris Claremont and Jim Lee, reported Aceshowbiz.
"Josh Zetumer just turned in the first draft of the script, and it's killer.
"None of us were sure how he was going to deal with the X-Men world. But we're going to be changing some of the tropes of these movies. It's always about saving the world (Laughs), All I can say is, I'm super excited," the "Magic Mike XXL" actor revealed.
Raised in New Orleans, he is also a thief who often speaks in a Cajun accent.
"Gambit" is set to hit US theatres on October 7, 2016 following the release of "X-Men: Apocalypse" on May 27, 2016.