Following a month-long hiatus coinciding with the Winter Olympics, "Marvel's Agents of S.H.I.E.L.D." is back with a new episode on ABC this Tuesday, titled "T.A.H.I.T.I." That's not all that's new: The episode also sees the debut of veteran actor Bill Paxton as John Garrett, a S.H.I.E.L.D. field agent who has a long history with Phil Coulson (Clark Gregg).

One week later, Jaimie Alexander will guest star in her "Thor" and "Thor: The Dark World" role of Asgardian warrior Sif, representing one of the strongest unions yet between "Agents of S.H.I.E.L.D." and the Marvel Studios film franchise (beyond Marvel movie mainstay Gregg starring in the show, of course).

Paxton and Sif's appearances follow the recent revelation that Mike Peterson (J. August Richards) -- part of the show since the pilot -- is now the show's version of Deathlok, the most famous Marvel Comics character to be introduced on the show yet.

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CBR News spoke with "Agents of S.H.I.E.L.D." executive producers and showrunners Maurissa Tancharoen and Jed Whedon about all of the above and more, including the May (Ming-Na Wen/Ward (Brett Dalton) relationship, the recent mysteries surrounding Sky (Chloe Bennet) and the show's early mixed reception from critics and fans.

CBR News: Maurissa, Jed, let's start with arrival in this week's episode of Bill Paxton as John Garrett -- is there anything more you can share at this point about the role he's going to be playing on the show?

Jed Whedon: We're never allowed to share anything. [Laughs] We're so well-trained at this point that when people ask us questions, we just close our mouths.

Maurissa Tancharoen: We close our mouths and our brains explode because we can't compute what we're allowed to say and what we're not allowed.

Whedon: We can say that his character's a lot of fun. In just initially talking about the character, his name came up of dream choices to play someone with this sort of attitude about S.H.I.E.L.D., as a contrast to Coulson. Coulson's always been the company man with a dry sense of humor, whereas Garrett's a guy who never wanted to wear the tie, never wanted to be behind a desk. He's in the field because he likes being in the field. He likes blowing things up.

Tancharoen: He likes getting his hands dirty.

Whedon: Their friendship and back-and-forth has been a real pleasure to write, and seeing Paxton do it every day -- we're having a blast.

Since he's on board for multiple episodes, what's it like dropping an actor like Bill Paxton into a show like this? How does it affect the dynamic of the episodes he's in?

Tancharoen: It's been a lovely surprise, because he just fits right in. It's really nice to see Clark have someone that he's sort of palling around with. Of course, there's the initial few days when everyone is very enamored with Paxton -- he's regaling us with all of his stories from being in every single movie ever known to man. [Laughs] Telling us how he's been killed by a Terminator, an Alien and a Predator. He's the only guy who can claim that title. [Editor's note: Lance Henriksen joined this club following 2004's "Alien vs. Predator."]

We definitely developed the part with him in mind, and then the day when he was actually on set playing the part, it just all fell into place and made complete sense. Bill Paxton is Bill Paxton, and brings what Paxton does to any role. It's really fun now in the room to break his stories and his dialogue, and it's really fun to see our characters play off of a guy who definitely has a distinct personality from the team we've established on the show. It's a nice contrast, as well as a nice source of tension at times. There's a lot of drama and comedy to be mined from the relationship we build with him.

Fans are fairly obsessed with seeing characters from the comic books on the show, and since John Garrett does have a history in the comics, how did you arrive at using that character specifically?

Whedon: The character came out organically. We knew we wanted someone to come into this episode, and we knew the niche we were trying to fill in terms of a character we wanted to have on our show. We talked about various people from the comic book universe that it could be, and Garrett was the right fit. He's got the attitude we were looking for, and he was on the list of people we could use. [Laughs]

Tancharoen: To just be blunt, there is a list of characters we can use, and his name was on there, and then he happened to serve the purpose we were looking for.

Sif meets Lola in Upcoming "Agents of SHIELD" Episode

Speaking of characters, a major one is going to be guest-starring in next week's episode -- Sif. How significant is it to have a major, recognizable visible character from the Marvel movie franchise, other than Coulson, on "Agents of S.H.I.E.L.D."? It's something people had been hoping for since the start, so how big of a deal do you see being able to deliver that?

Tancharoen: It's really exciting for us to be the ones who allow audiences to get to know her a little bit more. In the "Thor" movies she's one of the players, but here, she has many, many scenes with our characters. Seeing the way she interacts with them, and also knowing her perspective, and why she's here, and her moral compass -- that was very fun, to be able to dive into that.

It's also incredible to see one of the Asgardian characters on our set in the full armor. Jaimie already is fairly tall, and then you put her in her Asgardian warrior boots, and she just towers over everyone.

Whedon: We had been excited to have an Asgardian from the films on our plane, because the fish out of water stuff in "Thor" was some of the best stuff, and also because Coulson is a little bit of a fanboy. An actual Asgardian in his midst -- we were excited for that, and it definitely played out just the way we had hoped. She's a pleasure to work with, and that also made it much easier, once she stepped on the set and was totally game for anything, it makes it a pleasure to write for her.

Since "Agents of S.H.I.E.L.D." has been so focused on the more grounded side of these fantastic things that are happening, how much is this episode different than the rest so far, by having someone who is very much a full-costumed comic book character in the mix?

Whedon: Initially, when we started the show, we had to be respectful to the films, so we didn't want to front-load it with a bunch of characters like that. In the Cinematic Universe, there are so few heroes that live on Earth and are humans, and we didn't want to all of a sudden say, "Yeah, but really there's a ton of them." Now that we've spent the time building to it, she can drop into our world without us having to talk for 20 whole minutes, "Oh my god, an alien just landed." It was different in that we didn't have to comment on the fact that she has full body armor and that she's from another planet, because we've spent enough time with our people. But it's also just a great one for the tone, which we like to vary on our show -- go back and forth from action to comedy and drama. We got a nice mix of all of it with her, I think.

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It's recently been established Mike Peterson is the show's version of Deathlok, which is certainly a big deal to hardcore comic book fans. There's only been a hint of him in this role so far, but can viewers expect to see him play a major parts in upcoming episodes?

Tancharoen: Yes. You'll be seeing Deathlok on the show. [Laughs] Quite a bit.

Whedon: We're excited for J. August to get to play that, and we're excited that he can finally tell people about it.

Of the many comic book characters that have been introduced on the show, Deathlok is the biggest name -- he's been around for decades, and has headlined several series -- is that as big of a name as fans should expect on the show for now? Or is there a possibility for additions around that level, or maybe even a little higher?

Tancharoen: If they're excited about Deathlok, then they should be excited about the things to come.

Whedon: We're in a weird spot, because if the character is big and cool enough, then they're probably planning a movie. [Laughs] We have a fairly large list of characters that we have at our disposal, and we plan on exploring all of them.

Let's talk about the revelations from recent episodes. There's a lot going on with Skye -- she got shot, and was revealed to be a "0-8-4" -- object of unknown origin. Originally, the character was positioned as very much the everyperson -- was it always the plan to have a slow mystery revolving around her, and establish that she was more than she appeared?

Tanchaoren: There were always plans for Skye. She was sort of under the guise initially as, "Here I am as the audience proxy," the girl who hates the establishment. As people have learned, there's more to her than that.

Whedon: And there's more to be learned!

Another development from the past handful of episodes is the physical relationship between May and Ward. You don't see a lot of representations in the media with an older woman and a younger man, and it's happening here, and that's definitely not the point of it. Was it deliberate to bring that point out, or just a byproduct of the storyline?

Tancharoen: It was definitely a choice that we made, and it seemed like an organic development to us, because they're two people who are cut from the same cloth. If any two people on the bus would be in it just for the sex, May and Ward would be the ones who would be capable of pulling that off. Their no-strings attached, compartmentalized way of living -- it seemed like it was a likely pair.

As far as the age difference, none of us found it jarring. There may be an age difference, but that happens all the time, one; and two, Ming is an incredibly beautiful woman that transcends any sort of feelings that come with the concept of age. It just made sense: She's super sexy, he's super sexy, they're both incredible warriors, and their sex came out of a place of shared pain. It just made sense to us.

"Agents of SHIELD" Crew Opens Up on Criticism, Expectations & the Remainder of Season One

To get a little reflective, the show had such high expectations from the start that inevitably some people didn't get what they wanted, and you saw that reaction a lot, from both critics and fans. From the last handful of episodes, and some of the announcements that have come out, there does seem to be a change in attitude towards the show -- have you noticed that? Is that encouraging, or did you always suspect it might be the case; that people would come around as the show progressed and found its voice a little bit more?

Tancharoen: There were times when we wanted to say, "Just wait for the back half!" It was always part of the plan to lay down a foundation and then bear its fruits in the back half. We're happy that people are responding to it positively. We're happy that people are enjoying the plan. It seems like it's working.

Whedon: There were many reasons that we built the season that way -- as I've said before, out of respect for the films and not wanting to overload a universe that has taken its time with big movie franchises with a bunch of heroes and people with powers. But we did try to plant the seeds and weave a web that's not all coming together. We're happy that people are responding well to something that we've been waiting to happen for a while. We're über excited about the stuff that's coming up. We think it's only going to get better.

You've stated there was a plan all along and you're sticking to it, but are there things that you're approaching differently now following lessons learned over the course of this first season?

Whedon: With any first season show, there's a huge learning curve.

Tancharoen: We were experiencing the inevitable growing pains -- and we still are. We're still learning what works, what doesn't, still are honing the process of even getting these episodes done within eight days. We have a very accelerate post-production process that involves them accomplishing these effects that are mind-blowing in just a short amount of time. We are being very judicious. We've learned what not to do, and will continue to learn how to make it all work.

Whedon: In terms of storytelling, we are always adjusting, just like a band playing a concert. You want to play the things that make the audience cheer. The ship's still headed in the same direction; all of our plans are finally coming to fruition. But you always make little adjustments, and if people are responding to certain things, you want to do more that. I think in the back half, it sort of all comes together for us.

Any final things you might want to tease in upcoming episodes?

Tancharoen: We have some other very fun guest stars in the pipeline.

"T.A.H.I.T.I.," the latest new episode of "Marvel's Agents of S.H.I.E.L.D.," airs 8 p.m. Tuesday, March 4 on ABC.