Blair Underwood will join the cast of Agents of S.H.I.E.L.D. as an important player in Agent May’s past.

Forget the alien writing, one of the biggest mysteries on Agents of S.H.I.E.L.D. is the taciturn and secretive Agent Melinda May (Ming-Na Wen.) But a new piece of the puzzle is settling into place now that actor Blair Underwood has signed on a pivotal player in May’s past.

Underwood will join the cast of Agents of S.H.I.E.L.D. as May’s ex-husband, Dr. Andrew Garner. The role is reported to be a recurring one, so any demons May may harbor for this old relationship will most likely not be swept away quickly.

Underwood, an established theater actor, has been nominated for Golden Globe awards for his work on L.A. Law and HBO’s In Treatment. He also starred in last year’s short-lived drama, Ironside.

The subject of Agents May’s ex-husband has been raised before on Agents of S.H.I.E.L.D., albeit subtly. May mentioned a previous marriage during her polygraph test in season 1, and this year suggested to Bobbi Morse that she was no longer in contact with her ex.

Of course, questions still bubble around the circumstances of this relationship. Who is the man who could successfully woo the austere Melinda May? Is he connected with S.H.I.E.L.D.? Was their relationship established before the scarring – and perpetually mysterious – events of Bahrain? Did May’s trauma corrode their love, or were other factors at play?

Fans will have to wait until Agents of S.H.I.E.L.D. returns from its winter hiatus to (hopefully) learn the answers to these questions. The actors are more privileged, however – Underwood will reportedly begin filming alongside Min-Na Wen this week.

Agents of S.H.I.E.L.D. will return on March 3, 2015.

What do you think of May’s ex-husband appearing on ‘Agents of S.H.I.E.L.D.’?