For those of you who enjoyed the 2010 family-friendly Greek mythology flick Percy Jackson & The Olympians: The Lightning Thief, a sequel is on the way for release in 2013.

Stars of the first movie Logan Lerman, Alexandra Daddario, Brandon T. Jackson, and Jake Abel are all set to return, and now Fox 2000 is assembling some supporting cast for the sequel, which will be titled Percy Jackson & The Olympians: The Sea of Monsters.

It’s being reported that fanboy favorite Nathan Fillion, star of Firefly and Castle, has joined the cast. The actor will be playing the Greek god Hermes, messenger of the gods and father to Abel’s character, Luke. Dylan Neal played the much smaller role in the first film.

Thor Freudenthal (Diary of a Wimpy Kid) will be directing the sequel, stepping in for The Lightning Thief director Chris Columbus, who will be acting as a producer this time around.

[Source: THR]