Michael Raymond-James

True Blood alum Michael Raymond-James has landed a recurring role on the upcoming second season of Once Upon a Time, TVGuide.com has confirmed.

Details about his part, which was first reported by Entertainment Weekly, are being kept under wraps, with reps for the ABC series calling his role a "mysterious new character."

With Lancelot, Mulan and Sleeping Beauty all recently cast -- as well as Hook -- it's odd that ABC is keeping mum on this presumed fairy-tale character. Therefore, we're going to offer up our own theories on who the Terriers star will play.

One Upon a Time casts Captain Hook

Could he be Henry's biological father, whom executive producers Edward Kitsis and Adam Horowitz promised would be revealed in Season 2? Maybe he's Rumpelstiltskin's grown-up son Bae, whom the producers also hinted may appear in the sophomore run. Or he could be the Jack of Jack and the Beanstalk, who is expected to pop up this year as well.

Keeping secrets isn't new for the ABC fairy-tale drama. In Season 1, when TVGuide.com broke that Sebastian Stan will guest-star, the producers initially kept quiet. It turned out he was playing the pivotal role of the Mad Hatter from Alice in Wonderland.

Who do you think Raymond-James is playing? Hit the comments with your thoughts.

Once Upon a Time returns Sunday, Sept. 30 at 8/7c on ABC.