UPDATED: The Passage, Fox’s high-profile drama pilot from Liz Heldens, Matt Reeves, Scott Free and 20th Century Fox TV, will film after the end of the current pilot season.

I hear the decision was made early on based on the scope of the project, an adaptation of Justin Cronin’s fantasy book trilogy, which requires longer lead time as it involves an elaborate production and visual effects.

The network and studio recently tapped top drama pilot director Marcos Siega to direct the pilot, securing permission for him to do the project from Warner Bros. TV, where he is under an overall deal, serving as  director/executive producer on new ABC series Time After Time after directing the pilot. (His pilot directing credits also include WBTV’s Blindspot, The Following and The Vampire Diaries.)

Written by Heldens, The Passage begins as a character-driven government conspiracy thriller and morphs into a post-apocalyptic saga with vampires. The series spans more than a century and focuses on a young girl named Amy who must save the human race.

Heldens executive produces alongside Reeves and Adam Kassan via 6th & Idaho, Siega, and Ridley Scott and David W. Zucker via Scott Free Productions. Cronin is co-producer.

Cronin’s The Passage trilogy includes the best-selling eponymous first book, published in 2010 by Random House’s Ballantine Books, which was followed by The Twelve in 2012 and The City of Mirrors last year.