HBO has greenlit the long-brewing miniseries Lewis and Clark, adding Belgian actor Matthias Schoenaerts in a title role, alongside Casey Affleck. According to Deadline, Schoenaerts (The Drop, The Loft) will play William Clark while Affleck (Interstellar, Gone Baby Gone) will portray Meriwether Lewis.

Based on Stephen E. Ambrose's 1997 book Undaunted Courage, Lewis and Clark follows the famous explorers as they search for a fabled all-water route to the Pacific Ocean. Charged by President Jefferson to explore the country west of the Mississippi, they encounter new terrain and the native tribes living there. The series will not only highlight the duo's discoveries but their physical, spiritual and emotional journey.

"In Lewis and Clark, we can see American idealism and the breathtaking natural beauty of the continent, as well as the complexities and tragedies of what came to be known as America’s 'manifest destiny,'" Michael Lombardo, president of HBO Programming, said in a statement.

Tom Hanks, Gary Goetzman, Edward Norton, Brad Pitt, Dede Gardner, Tim Kelly and Adam Leipzig are attached to the project as executive producers. The six-hour miniseries begins filming this summer.