(MTV)

Fans of "Agents of S.H.I.E.L.D." have a lot to be happy about. For the past few weeks, there have been various reports speculating about the upcoming season's cast and release date, though all the rumors had remained unconfirmed so far. However, Marvel has finally announced who would be returning to "Agents of S.H.I.E.L.D." season 3.

"Agents of S.H.I.E.L.D.", which first aired in September 2013, is a Joss Whedon TV series based on the Marvel Comics organization, S.H.I.E.L.D. Initially, the series followed Phil Coulson as he embarked on assembling a team of S.H.I.E.L.D. agents to handle strange new cases.

The ABC show has received generally favorable reviews with the series becoming Tuesday's top show for men aged 18-49. The storyline of "Agents of S.H.I.E.L.D." is heavily influenced by Marvel films. Critics and casual fans of the show are impressed with the way it marries details from the films and books, with Zap2it even going so far as to say "the show is game-changing in terms of how the mediums of film and television can be interwoven."

The upcoming season of "Agents of S.H.I.E.L.D." is likely to be just as entertaining as the previous two, especially since recent reports have confirmed that fans will be seeing more of Agent Mack and Lincoln Campbell. Earlier this month, TV Line had announced that Henry Simmons and Luke Mitchell had been promoted to series regulars. Executive producer Jeff Loeb even went so far as to gush about Mitchell's pivotal role in the upcoming season, saying:

"Luke proved a valuable addition to our cast in Season 2, and after seeing him light up the screen with his charisma we knew we had to have him back for more. Our writers have come up with big plans for the character of Lincoln in our next season, and we can't wait for fans to see everything we have in store."

"Agents of S.H.I.E.L.D." season 3 premieres on September 29 on ABC.