Ghost Whisperer star David Conrad has signed on for a top secret role in Marvel's Agents of S.H.I.E.L.D., which we reported earlier this month is debuting on Tuesday, September 24 at 8 PM ET on ABC.

The actor will appear in a recurring role in the series, but it isn't known how many episodes he has signed on for. While this is far from a confirmation of his character, Marvel has been searching for an actor to play a brilliant and quirky scientist in his mid-40s, which matches the actor's description. He joins a cast that includes Clark Gregg, Ming-Na Wen, Brett Dalton, Chloe Bennet, Iain De Caestecker, and Elizabeth Henstridge.

Joss Whedon directed the pilot episode and co-created the series with Jed Whedon and Maurissa Tancharoen. The trio will also executive produce alongside Jeph Loeb and Jeffrey Bell.

We'll keep you posted about this mysterious character as we near closer to the series premiere debuting this fall.