When TVLine visited the Marvel’s Agents of S.H.I.E.L.D. set in December, Chloe Bennet spoke of how Daisy has been mourning former director Phil Coulson. At the time — as with many things Marvel — one had to wonder if semantics were at play. But as since has been double-secret confirmed, the team’s director did in fact succumb to his fatal affliction.

“I wasn’t lying,” Bennet said when we reconnected at ABC’s TCA party earlier this month. “We have been mourning Coulson.”

And yet, Clark Gregg will be back for Season 6 (premiering in May), news that only recently came to the fore. “It’s been weird having to stay quiet,” Gregg shared with TVLine. All told, “This has been a weird one because we’re not on the air, we’re taking a year off… and because Season 6, you’ll see, takes a lot of chances, once again.

“And it’s a little weird to not have ever seen any of it,” he added. “I’m nervous!”

In keeping secret Gregg’s return, Bennet and castmate Elizabeth Henstridge said that everyone “was very paranoid about even getting any glimpse of him on social media, on set….” Added Gregg, “We take it pretty seriously,” as “a kind of trust exercise.”

One concern was that news of Gregg’s return would discount the emotional heft of how things were left, with Coulson being dropped off in Tahiti, Melinda May at his side, to live out his final days.

“We thought the stuff in Season 5, and the way it ended, was really heavy, and beautifully done, and beautifully written, and we didn’t want to buy that back cheaply,” Gregg explained. “And I don’t think they did. What they’re doing doesn’t betray that, so we were happy to keep the secret until it felt appropriate.”

When told that some fans were declaring a Season 6 without Gregg as not S.H.I.E.L.D. at all, Henstridge interjected, “That’s what we were saying, too!” Being the Marvel Cinematic Universe character on whom the TV series was spun off, “We would not have a show without Clark, we wouldn’t have a show without Coulson,” Bennet nodded. “They were rightly upset.”

After quipping that Henstridge and Bennet were “very well-trained” to say those “very kind” words, Gregg said that he was surprised they “brought me, Clark, back, because there are so many amazing characters and relationships on this show now. I really think people would have been like, ‘Wait! Wait! Where’s– Oh, oh, this is cool,'” and forget all about him. With a nod to his costars, he smiled, “I’ve been very happy to keep throwing with these people.”

Exactly who or what Gregg will be playing in Season 6 is one of those Marvel secrets still very much under wraps. (A Season 6 promo only shows the character in ominous profile, while he can be heard claiming to not know what S.H.I.E.L.D. is.) Will the same fans who clamored for Gregg’s return wind up heartbroken by what they find in Coulson’s stead? “They might be a little disturbed,” the actor warned.

Bennet then added, “They won’t realize how much of Phil is really Clark, and how much of a departure this new character is. To see Clark do something very, very different, I think, will actually be a fun treat for fans to see.”