Justin Theroux has joined the cast of Cary Fukunaga's upcoming Netflix series Maniac. While Theroux has been a Hollywood regular since the 90s -- appearing in dozens of films and TV shows -- arguably his greatest role to date was his most recent one, that being Kevin Garvey on the critically acclaimed HBO drama The Leftovers. Kevin began the series as a small-town sheriff struggling with the break up of his family, but went on quite the amazing journey of personal discovery over The Leftovers' three seasons, with Theroux giving a tour de force performance.

With The Leftovers now over, Theroux won't be staying away from the small-screen for long, with production on Maniac's 10-episode debut season already underway. Hailing from True Detective season 1's Cary Fukunaga -- who will both executive produce the series and direct all 10 episodes -- Maniac is based on a 2014 Norwegian series of the same name. Starring in Maniac are Emma Stone and Jonah Hill, who will also produce alongside Fukunaga.

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Described as a dark comedy, Maniac stars Stone and Hill as patients in a mental asylum, with a majority of the season taking place inside their personal fantasy worlds. Theroux will play a character named James Mantleray, and is set to be a recurring guest star on the series. Mantleray is rumored to be an alcoholic mad scientist, but official character details have yet to be confirmed.

One factor that seems likely to have played a role in Theroux coming aboard Maniac is the presence of Patrick Somerville, who is set to write and executive produce three of Maniac's  episodes. Somerville played a similar role on The Leftovers, personally writing four episodes, and co-producing ten. With the success Theroux had on The Leftovers, it makes perfect sense that he'd want to remain associated with people he worked with there.

In addition to his small-screen work, Theroux also has two notable film gigs coming up. He voices villain Garmadon in the highly anticipated Lego Ninjago Movie, and will also star in director Duncan Jones' latest sci-fi effort Mute, alongside other heavy hitters like Alexander Skarsgård and Paul Rudd. That film will also be a Netflix release, so it appears that Theroux might slowly be carving out an ongoing relationship with the streaming powerhouse.

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Source: IndieWire