The CW drama stars Britt Robertson as Cassie, a young girl who discovers that she is a witch.
Dekker has signed up to play Adam, a member of Cassie's coven and a possible love interest for her.
Speaking to TV Guide, Dekker explained that he is optimistic that the project will be picked up.
"I think that the [LJ Smith] books are very popular, which I didn't know even when I signed on for it," he said. "Obviously it's [executive producer] Kevin Williamson and CW again, who [are] behind The Vampire Diaries and Dawson's Creek, so I think there's a lot of belief that it will be in that vein.
"I have to say I had an amazing time doing the pilot. I'm very hopeful and pretty sure that we'll be back for at least one season. I haven't done TV for a couple of years now. It's a grind - it's a lot of hard work, but it's really rewarding."
Dekker also joked that viewers should tune in because there is a "steamy moment in the middle of the pilot".
"I joked [it] was our Twilight moment," he said. "I have to run after Britt Robertson and in the rehearsal I kept calling her Bella."
Secret Circle will also star Ashley Crow, Natasha Henstridge, Louis Hunter, Phoebe Tonkin, Gale Harold, Shelley Hennig and Jessica Parker Kennedy.
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