In the lead-up the premiere of third season of "Marvel's Agents of SHIELD," ABC has released the plot synopsis for the season's second episode titled "Purpose in the Machine."

Fitz and the team enlist the aid of an Asgardian to unlock the secrets of the ancient monolith that swallowed Simmons, and Agent May is at a crossroads in her personal and professional life.

"Agents of S.H.I.E.L.D." already announced a "Secret Warriors" storyline for season three. In the "Secret Warriors" comic series by Brian Michael Bendis, Alex Maleev, Jonathan Hickman and Stefano Caselli, Daisy Johnson (a.k.a. Quake) leads a sleeper team of superpowered peers called a caterpillar team. After Terrigen was exposed to the general population at the end of "S.H.I.E.L.D.'s" second season, leading to an anticipated boom of Enhanced people, it seems as though Skye will get her own sleeper super team in the show -- something that was teased when Coulson handed her a blue folder labeled "Caterpillar" in the season finale.

"Agents of S.H.I.E.L.D." season three premieres Tuesday, September 29 at 9 pm EST on ABC.