"Marvel's Agents of S.H.I.E.L.D." is set to return this fall for its fourth season on ABC, and the series -- which originally debuted at 8 p.m., before moving to an hour later -- will now air at 10 p.m. on Tuesdays. While that may not seem like all that big of a deal in today's era of DVRs and streaming, Head of Marvel Television Jeph Loeb told CBR that it will have a definite effect on the show, which will now have a bit more "edge" and "grit."

"By going to 10 o'clock, we're going to be taking on just a little bit more edge, a little bit more grit," Loeb told CBR in a video interview last month at Comic-Con International in San Diego (watch the full interview above). "The show is pretty violent for something at 9 o'clock, but when we get to 10 o'clock, we're going to be just a little hair of something that I think people are going to really enjoy."

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While it remains to be seen what a slightly edgier and gritter "Agents of S.H.I.E.L.D." will look like, there are multiple storyline changes coming in season four that are already apparent. The previous season ended this past spring with the revelation that Daisy Johnson (Chloe Bennet) was no longer part of S.H.I.E.L.D. and operating under the media-given name of "Quake" (the same as the character's code name in the Marvel Comics), and that Phil Coulson (Clark Gregg) was no longer director of the always-turbulent superspy organization.

It's since been revealed that actor (and veteran Batman voice performer) Jason O'Mara will play the group's new director in season four (though his character name has yet to be revealed), and that Gabriel Luna will play Robbie Reyes, better known as the most recent incarnation of Ghost Rider -- the biggest Marvel superhero yet to be introduced on "S.H.I.E.L.D."

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"You got a little tease at the end of last season that clearly something's happened to Daisy," Loeb said. "She seems to be on her own. That dang media has decided to name her Quake, so we have to find out if that's a good thing or a bad thing -- and clearly, S.H.I.E.L.D. is now hunting her. We're seeing that Coulson and Mack [Henry Simmons] are now partners for some reason; they refer to each other as though they are equals. They refer to Phil Coulson as 'Agent Coulson.' They refer to 'the new director.' There are obviously going to be a lot more changes."



Since "Agents of S.H.I.E.L.D." debuted in 2013, Marvel Television has launched shows like the fan-favorite "Agent Carter" -- which ran for two seasons on ABC -- and popular and acclaimed Netflix series "Daredevil" and "Jessica Jones." But while "S.H.I.E.L.D." might be Marvel TV's longest-running show, it's also one that retains a special place in Loeb's heart, especially given what its success meant to future projects.

"People ask me all the time, what's my favorite show of all the shows that we do," Loeb told CBR. "I really do have a very special place for 'S.H.I.E.L.D.' Without 'S.H.I.E.L.D.,' nothing else happens. We had to prove to the world that Marvel Television could make a television series, and that we could compete in this incredibly competitive atmosphere. Yes, we had an incredible gift that Clark Gregg came from features and reprised his role as Phil Coulson. but all those brand-new characters, all those people that [executive producers] Jed Whedon and Maurissa Tancharoen and Jeff Bell work with every single time, the fans out there who so embraced our entire cast -- all that makes a huge difference."

"Marvel's Agents of S.H.I.E.L.D." returns 10 p.m. Tuesday, Sept. 20 on ABC.