Development studio Cloud Imperium Games unveiled details of the campaign mode for "Star Citizen" during this year's CitizenCon, an event held annually for the game's fans.

According to the studio, the game's "Squadron 42" single-player mode features an all-star cast including Gary Oldman, Gillian Anderson and Mark Hamill, IGN reported.

Aside from providing their voices to the game, the actors also lent their likeness through motion-capture technology.

Oldman, who's been appearing in various television and film projects for more than 35 years now, will take on the role of Admiral Ernest Bishop in "Star Citizen." According to his character's description, Admiral Bishop is a cunning tactician and a valuable asset to the United Empire of Earth Navy.

"A lifelong soldier, Bishop quickly distinguished himself as a leader and strategist by seeing angles that others don't and taking risks that others won't," the developer wrote on its website. "Strategy is a shifting puzzle to him."

"For better or worse, he is capable of disconnecting his empathy to the point where a battleship is simply an asset [with strengths and weaknesses] in the game, not a ship of five hundred souls," the studio added. "This is how he keeps winning."

Joining Oldman in the game's cast are Gillian Anderson, who's known by her fans as Dana Scully from the "X-Files" television series, and Mark Hamill, who played the iconic Luke Skywalker in the "Star Wars" films.

Details about their characters in "Squadron 42" are still unclear but sources reported that Anderson was casted to portray Admiral Bishop's daughter.

This is not the first time that these three actors worked on a video game. Oldman voiced the villain in "Lego Dimensions" and other characters in various "Call of Duty" games while Anderson reprised her role as Scully in "The X-Files Game" and "The X-Files: Resist or Serve." Hamill, on the other hand, has worked on various titles including "Crash Bandicoot," "Call of Duty 2: Big Red One" and "X2: Wolverine's Revenge."

Rounding up the cast of the game's campaign mode are Sophie Wu, Mark Strong, Sandi Gardiner, Craig Fairbrass, Liam Cunningham, Ben Mendelsohn, Ian Duncan, Jack Huston, John Rhys Davies, Rhona Mitra, Gemma Whelan, Harry Threadaway and Andy Serkis.

There is still now exact release date yet for "Squadron 42" but the studio is targeting to release it sometime in 2016. Gamers can already start pre-ordering the single-player mode through the studio's website.