Nathan Fillion is perhaps already a god to his many devoted fans, but now he's about to play one. Fillion, star of geek favorites like the 'Firefly' TV series, its big screen spinoff 'Serenity' and the cult horror hit 'Slither' has signed on to star in 'Percy Jackson and the Olympians: The Sea of Monsters', the follow-up to 2010's 'Percy Jackson and the Olympians: The Lightning Thief'.

The Hollywood Reporter revealed that Fillion will star as the Greek god Hermes.  Fillion's Hermes - who was played by Dylan Neal in the first movie - is the father of the returning character Luke, again a villain in the story.

Based on the second book in Rick Riordan's series of young adult best sellers, the new movie is being directed by Thor Freudenthal. Chris Columbus directed the first installment and is producing this one.

Logan Lerman is returning as the title hero, while other cast members include fellow returning stars Alexandra Daddario, Brandon T. Jackson and Jake Abel.

The question is: was anyone clamoring for a second 'Percy Jackson' film? The first one grossed $88 million in the U.S. and ended up with a total of $226 million worldwide - just enough to turn a small profit on its $95 million budget. But it never felt like the kind of film people kept talking about, and reviews were mixed as well.

We'll find out if that demand is there when 'The Sea of Monsters' arrives in theatres on March 27th, 2013. At any rate, Fillion fans will at last get to say that their hero really is godlike.

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