"Avatar" actor Sam Worthington and "Orange is the New Black" actress Taylor Schilling have joined the growing cast ensemble of Lennart Ruff's upcoming sci-fi film "The Titan."

According to Deadline, Worthington is set to star in Ruff's "The Titan," prior to his reprisal of Jake Sully in James Cameron's upcoming "Avatar" sequels. The publication added that Schilling has done filming "Orange is the New Black" season 4 and Greg Kinnear's "Phil" before her appearance in "The Titan" was confirmed.

Aside from Ruff's "The Titan" and Cameron's "Avatar" sequels, Worthington is also set to appear in Mel Gibson's historical biopic "Hacksaw Ridge," Kriv Stenders' war drama "Danger Close," and Stuart Hazeldine's drama film "The Shack," among others.

About "Avatar 2" and the other sequels, Cameron told Entertainment Weekly that he was currently in the process of doing another pass through all three scripts and just refining them. He added that that was in parallel with the design process, which he described as "very mature" at the moment.

"The Titan" follows a military family who takes part in a ground-breaking experiment of genetic evolution and space exploration. Aside from Worthington and Schilling, the sci-fi film also stars "Kingsman: The Secret Service" actress Sofia Boutella and "Batman Begins" actor Tom Wilkinson.

With Ruff at the helm of the film, "Simply Plimpton" and "Hell on Wheels" writer Max Hurwitz is on board to pen the film screenplay based on Arash Amel's story. Amel, Rory Aitken's 42, Ben Pugh, and Brian Kavanaugh-Jones' Automatik are in charge of the film's production.

Fred Berger is set to executive produce the film, which will be financed by Leon Clarence and Motion Picture Capital. Voltage Pictures and CAA will handle international and domestic sales, respectively. "Bastille Day" casting director Julia Harkin will also be the casting director for Ruff's "The Titan."

With Ruff's "The Titan" in its early phase of development, exact details on the plot, additional characters and cast members, and release date are yet to be revealed.