The Guardians are back. Production on "Guardians of the Galaxy Vol. 2" is now underway in Atlanta and, like with all Marvel movies, a shroud of mystery surrounds the highly anticipated sequel. After becoming a surprise box office success (it's the fourth highest-grossing Marvel Studios movie ever), plenty of attention was given to what Star-Lord, Gamora, Drax, Rocket and Groot would do next. We do know, thanks to a dynamic new team photo, that the Guardians are just as rock and roll as ever.

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We'll find out in just over a year when "Guardians of the Galaxy Vol. 2" lands in theaters on May 5, 2017, but there's actually a lot we already know thanks to the countless interviews writer/director James Gunn, Marvel Studios president Kevin Feige and the film's cast have given over the past year and a half. Here's the tale of how "Guardians of the Galaxy Vol. 2" came to be, and here's what we know so far.

WHAT DO WE KNOW ABOUT THE STORY?





James Gunn was confirmed as the writer and director of the initially untitled "Guardians of the Galaxy" sequel way back in July 2014; this actually was announced before the first "Guardians" opened -- that's how good of a feeling Marvel Studios had about it. He first talked about the script a few months later in November 2014, saying, "I had the basic story for number two while I was working on number one, and perhaps even beyond that." He had the entire story written by December 2014 and had completed 70 pages of the script by April 2015. He finished the first draft in May 2015, the second draft in September 2015, and the final draft in January 2016.

James Gunn's pitch for the sequel was apparently so good that it made Chris Pratt cry, the actor revealed in June. "I will say that [James Gunn's] pitch and his idea legitimately put tears in my eyes," said Pratt. "It is so good... I cannot wait to get started on it, and I cannot wait for people to see what he's going to pull off with this second movie. It's so, so big and so good."

Vin Diesel also heaped similar praise upon Gunn's work when he got a draft of the script -- along with a mix CD titled "Awesome Mix Vol. 2" -- in November 2015. "James Gunn is such a great writer," said Diesel. "I read this script and I go, you're such a great director and you're this great a writer too. No wonder Marvel is so excited about what you do. No wonder Marvel can't wait to see 'Guardians of the Galaxy 2.' It's one of those page-turners, you can't put the script down."

The title of the fim -- "Guardians of the Galaxy Vol. 2" -- was accidentally revealed by Marvel Studios president Kevin Feige in June 2015, and James Gunn officially confirmed it just hours later.

WHAT DO WE KNOW ABOUT THE PRODUCTION?





"Guardians Vol. 2" got its current release date, May 5, 2017, in October 2014 as part of Marvel's massive Phase 3 announcement. In April 2015, Gunn revealed that the film would begin production in February 2016 (accurate!) at Pinewood Studios in Atlanta. The production is scheduled to last for ten months. It was announced in August 2015 that Tyler Bates would return as the film's composer.

The first table read took place in late January 2016, and Chris Pratt Instagrammed his thoughts about the production (spoiler: he's grateful and excited!). Rehearsal pics of Michael Rooker, the cast, Star-Lord's Walkman and a Rocket stand-in popped up over the first week of February 2016. Day one of filming was on February 11.

WHAT'S UP WITH THE GUARDIANS OF THE GALAXY?





Early on, James Gunn indicated that the cast will undergo emotional changes. "[B]asically, James Bond is a James Bond movie over and over and over again," said Gunn in December 2014. "The character never learns anything, and the character never does anything new. And that's not a knock. It's a really fun series. But that's not what the Guardians are. The Guardians are going to continuously change. I think that some of the characters are probably worse than what we think they are, and other characters are better than what we think they are. It's going to be interesting to learn a little bit about that as time goes on."

In October 2015, Gunn shared that Drax won't be a big fan of Baby Groot and clarified Rocket's age as being in his late 20s "if he was a human." Vin Diesel revealed that same month that he's run the idea of a giant Groot by Gunn.

Zoe Saldana spent part of the week of Thanksgiving 2015 doing makeup tests for Gamora. Speaking of Gamora, Gunn has said that he's had conversations with Marvel making sure that Gamora is equally represented in merchandise this time around. "I had a big conversation about [Gamora merchandising] yesterday with one of my producers at Marvel about trying to make sure, especially that Gamora is represented more in stuff and all the 'Guardians' toys, but especially all the clothing and bed sheets and all that stuff," he explained in December 2015. "I think it's really important -- that often times it's something Marvel is concerned with, as I am. It's frustrating and stuff and so it bums me out."

Chris Pratt said in May 2015 that he is signed on for two more "Guardians" films as well as a couple other non-"Guardians" adventures, although he isn't sure what those other films could be yet.

And the first team pic of the Guardians was revealed on February 17, 2016.

WHAT ABOUT THE SUPPORTING CHARACTERS?





Gunn said back in July 2014 that he knows a lot of stuff about Xandarian and Kree culture, as well as the Krylorians and Ravagers, that could end up in the film. A few months later in November, he discussed the supporting characters from the first film that he wants to see more of, including Yondu, Kraglin, the Ravagers and Nebula. He was unsure about the Collector (Benicio Del Toro). Del Toro was unsure about his chances of return in July 2015 and again in January 2016. John C. Reilly's name came up in December 2015, but Gunn couldn't confirm that he'd return.

Nebula was confirmed as returning in April 2015 -- and Karen Gillan most likely won't have to shave her head this time. In November 2015, Gillan said that the film will flesh out her relationship with Gamora. "I think what I'm really excited about it delving into the sisterly relationship between Gamora and Nebula," said Gillan. "I think that we're going to see a little bit more of that, and it's going to be a bit more fleshed out."

Gunn even hinted at a return cameo from Stan Lee, in October 2015, saying, "I love Stan Lee. He's a great man. He's one of my favorite people in the world. I still get giddy like a school girl whenever I'm around him, and he's also nice to me, so why would I not want him in 'Guardians of the Galaxy Vol. 2?'"

WHAT DO WE KNOW ABOUT THE NEW CHARACTERS?





Overall, James Gunn has said that "Guardians of the Galaxy Vol. 2" will have a smaller cast than the first film. That being said, he also stated that he hopes to include more female characters in the film back in September 2014. He echoed that sentiment in May 2015, saying that he wanted to have at least two women on the core Guardians team and that he had someone in mind for the role.

Pom Klementieff joined the cast in October 2015, and a few days later a rumor appeared that she'll be playing the Guardians' martial arts master Mantis. Gunn confirmed that Klementieff is playing Mantis on February 17, 2016. Earlier in February, Gunn spoke about the cast member playing the new Guardians member (most likely Klementieff), saying, "We have a new cast member playing a new member of the Guardians of the Galaxy and she was the most awesome and easiest person I've ever had to cast, and blew me the fuck away. Really. She's amazing and I can't wait to share her with the world."

Kurt Russell was first rumored to be up for the role of Star-Lord's dad in Deceber 2015, and Russell said talks were happening a few days later. Russell was officially confirmed as part of the cast on February 17, 2016. Elizabeth Debicki and Chris Sullivan were also announced as part of the cast, although their roles are still unknown.

Curiously, Gunn said in March 2015 that one of his favorite Marvel characters would appear in the sequel and that fans shouldn't assume it's a man. Then, in June 2015, he said he had to cut a character he "really liked" from the script because it was getting "too busy."

WHO DEFINITELY ISN'T IN THE MOVIE?





Gunn has shot down a number of rumors regarding potential new characters appearing in "Guardians Vol. 2," including:

WHAT'S UP WITH STAR-LORD'S DAD?





He's in the movie, and Gunn mentioned that right away way back in June 2014. Kevin Feige confirmed this in August 2014. Gunn then clarified in February 2015 that Star-Lord's movie origin would be different from his comic book origin, and that he wouldn't use J'Son of Spartax. A rumor emerged in November 2015 stating that Peter Quill's father would be revealed as Captain Mar-Vell. Gunn emphatically denied the rumor, saying it would be the last rumor he would comment on.

WHAT ABOUT THANOS AND THE FILM'S VILLAIN?





Gunn said almost immediately, in August 2014, that Thanos would not be a major player in the film. "Thanos is not the most important thing in Guardians 2, that's for damn sure," he said. "There's the Guardians themselves and other threats the Guardians are going to be facing that are not Thanos." Feige also said that Thanos wouldn't be in the film in a December 2015 interview.

Not much else is known about the film's villains. A report surfaced in October 2015 saying that Matthew McConaughey passed on playing the villain, and a rumor emerged in January 2016 that Ego the Living Planet may pose a threat in the film.

THERE'S AT LEAST A CONNECTION TO "AVENGERS: INFINITY WAR," RIGHT?





Nope -- at least that's what Gunn has been saying since November 2014. "I don't feel beholden to that stuff at all," Gunn said. "I think it's really about the Guardians and what they are doing. We're not subservient to the Avengers. 'Guardians 2' is not a movie that's made to move toward 'Infinity War.' It's something that's made to move toward future cosmic movies, so I don't feel that that is something that affects me that much." Gunn also said that the Infinity Stones, which made a big appearance in the first "Guardians," are "not really a thing" in the sequel.

WILL WE GET "GUARDIANS OF THE GALAXY VOL. 3"?





Back in January 2015, Gunn said he had plans for "three other stories connected to Guardians" if he stays with Marvel for that long. By February 2016, though, Gunn was less certain about sticking around that long, saying, "Right now, I'm really excited and happy to be working with Marvel and doing 'Vol. 2' and then I'm going to decide what I'm going to do after that," he shared. "I've been offered a lot of stuff but I really just want to get through 'Vol. 2.'"

"Guardians of the Galaxy Vol. 2" is scheduled to open on May 5, 2017