'Agents of SHIELD' Team Talks "Supernatural" Season Premiere Twist, Possible 'Doctor Strange' Link

MARVEL'S AGENTS OF S.H.I.E.L.D - The Ghost -GABRIEL LUNA- Publicity - H 2016
ABC/Jennifer Clasen

[Warning: This story contains spoilers from Tuesday's season premiere of Agents of SHIELD.]

Agents of SHIELD doubled down on the supernatural in the season four premiere.

While viewers were expecting a touch of the mystical with the addition of Robbie Reyes aka Ghost Rider (Gabriel Luna), a twist in the episode revealed that a mysterious box has the ability to make people go crazy and homicidal after witnessing a ghost-like entity. And that box has somehow infected Agent May (Ming-Na Wen). 

So what's in the box?

"Weed," Wen joked an early screening of the episode held Monday. "Really good weed."

Executive producer Jed Whedon laughed, but then elaborated. "That's what in the box, something strange," he said. "We are introducing, with the addition of young Mr. Ghost Rider, we are introducing a different, supernatural element to the MCU in which happens to coincide with the release of Doctor Strange. Coincidence? So that's what's in the box. We can't tell you, but it's something along those lines."

Wen echoed the "We can't answer that question" line when asked how worried fans should be about May. "It's obvious that she is affected by it," the actress teased.

As for the other supernatural element of season four, Ghost Rider, Whedon revealed that they did take some liberties when it came to adapting the popular Marvel antihero for the show.

"We've obviously made a few changes you can see around the surface. We've aged both him and [his brother] Gabe up," Whedon said. "But we're pretty faithful to his backstory. We also don't want people who have read the comics to know what's coming next. We put our own spin on it. And we're super happy with everything we've been seeing from Gabriel in his portrayal in the role."

After coming in contact with Ghost Rider and witnessing his fiery abilities firsthand, a rogue and on-the-run Daisy (Chloe Bennet) tried to get him to kill her, believing that she "deserves to die" for everything that happened in season three. The Ghost Rider spirit clearly didn't agree with her, since he left her alive at the end of the episode.

"She's not doing well," Bennet said. "She's had a rough couple of years. She's taking some time and I think it's kind of her way of protecting the people that she cares about. Everyone she's gotten close to, something bad has happened to them. It's her weird, selfish way of protecting them, but we'll see."

Since SHIELD now airs one hour later, at 10 p.m., the showrunners said they are able to take the show in a more "mature" direction, as was already proven in the sexy opening shot of the season four premiere.

"There was a shot of Quake's legs … " Whedon said with a laugh. "[ABC] haven't really ever given us a note on violence. We've cut people into pieces and hacked them up and shot people point blank in the head. Never got any notes on that. So pushing the envelope for us will be in the sexual nature, as they say."

Marvel TV head Jeph Loeb agreed, adding, "I think what it does is give us the chance to tell different stories. The idea is some of the material might be more mature, there may be more grit, what we're doing might be darker. It certainly made a lot more sense when we wanted to introduce a character like Ghost Rider into this world. But it wasn't like it was completely unexpected. In many ways, it felt very organic to bring the team in in order to encounter this character."

As for former BFFs turned lovers, Fitz (Iain De Caestecker) and Simmons (Elizabeth Henstridge) have taken their relationship to the next level this season. But could Fitz keeping a secret as big as Dr. Radcliffe's (John Hannah) Life Model Decoy invention Aida (Mallory Jansen) pose a threat to their new relationship?

"It's weird. They're trying to maintain a healthy relationship while being secret undercover spies that have secret assignments," Caestecker said with a laugh. "I don't know, it's with the best intentions, keeping stuff from her, I suppose. It's going to get interesting. Lying is a strong word. I’m just keeping stuff from [her], not lying."

Agents of SHIELD airs Tuesdays at 10 p.m. on ABC.