Brett Dalton, Chloe Bennet, Elizabeth Henstridge and Iain De Caestecker might not be household names right now, but they likely will be by the time “Marvel’s Agents of SHIELD” Season 1 finishes airing in 2014. The foursome makes up the majority of the titular Agents of SHIELD in the upcoming ABC show, and though they’re joined by bigger names like Clark Gregg and Ming-Na, their characters add much of the show’s necessary depth.

Bennet made her ABC debut on “Nashville,” but her Skye is a different sort of character than what we’ve seen her play before. Skye is still a mystery for much of the series’ pilot, and her motives and history won’t be revealed early on in the season.

“She has an agenda, definitely. She’s a mystery,” Bennet tells Zap2it during a roundtable interview at San Diego Comic-Con, admitting even she doesn’t know her character’s secrets. “She’s definitely got some tricks up her sleeves.”

Dalton’s Grant Ward is more of an open book. He is a bit humorless in the first episode of “Marvel’s Agents of SHIELD,” but his interactions with Skye show his human side. “He’s not used to working as a team, so we see a lone wolf suddenly part of a wolf pack,” Dalton explains. He and Bennet tease that there could be some romance in their characters’ futures.

“What’s great about Skye and Ward is I think their characters are balancing each other out really nicely. They’re going to challenge each other, and it’s going to bring a lot of interesting chemistry to the show. A lot of interesting drama, maybe romance,” Bennet says. Dalton adds, “They probably hit it off on the wrong foot, but sometimes the people that get under your skin are really the people that challenge you, that make you change the most.”

Henstridge’s Jemma Simmons and Caestecker’s Leo Fitz offer up another sort of male-female dynamic on the show. These two are so close that they’re frequently referred to simply as “FitzSimmons,” leading some characters to believe that they’re actually one person. Instead they bonded while studying in school together, and now have a sibling dynamic that adds some humor to “Agents of SHIELD.”

“They are kind of one entity,” Henstridge says.

Though they were both experts of their majors at school, both Fitz and Simmons are thrown in over their heads when they enter the field as part of the “Marvel’s Agents of SHIELD” task force. Henstridge says the experience “knocks them.” Fortunately the duo has more seasoned veterans to turn to for advice, like Gregg’s Agent Coulson. Henstridge and Caestecker similarly turned to Gregg on “Agents of SHIELD’s” set.

“He sets the tone on set,” Caestecker says. “He’s very much about having a good time, but at the same time he’s about hard work and getting everything done. We want to make the best show we possibly can.”

The cast definitely has a good chemistry together, and that’s something Dalton credits to Joss Whedon. Dalton calls him an “alchemist,” and says, “He gets the right people together, and somehow we have the right chemistry.”

Though these characters are all agents of SHIELD and in the know about the supernatural and superhuman forces at work on Earth and beyond, don’t expect them to be entirely at peace with the mysterious things they deal with on this show. Caestecker says not all of them have entirely come to terms with a post-Chitauri invasion world.

“One side of it is the fact is set right after the Battle of New York in ‘The Avengers.’ The public awareness of that world being present, supernatural elements being present, everyone’s very aware of that,” he says. “At the same time, we do get very surprised and excited when certain things come up.”

So what can fans expect from “Marvel’s Agents of SHIELD”? “You’ll see these characters grow and you’ll see relationships happen and you’ll see these humans living in this world with superhumans,” Bennet says. “I think everyone can relate to not feeling good enough, so I think you’ll just see a really great, relatable, funny TV show.”

“Marvel’s Agents of SHIELD” premieres on ABC on Sept. 24.

Posted by:Terri Schwartz