The horror thriller stars Kevin Bacon as Ryan Hardy, an FBI profiler in pursuit of a deadly serial killer (James Purefoy).
"[Showrunner] Kevin Williamson, who created Dawson's Creek and the Scream franchise, he's the real deal," Reilly told reporters at the Fox US TV upfronts.
"He pitched us a highly serialised show [about] tracking down a serial killer. The pilot ended up being incredible.
"It's going to play for 15 weeks straight and... we think it's going to be the next 24."
Reilly added that he was thrilled to sign X-Men: First Class star Bacon for the show's lead role.
"There are more and more big stars who are intrigued by doing TV," he explained. "For us, it worked. His needs fit our needs."
The Following will premiere on Fox in 2013.
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Watch the trailer for The Following below: