Hell on Wheels type TV Show network AMC

In the season three finale of AMC’s Hell on Wheels, Elam (Common) went searching for kidnapped Cullen (Anson Mount) and stumbled upon a bear instead. Out of bullets, he was last seen losing that battle. Considering Common’s not in the first official cast photo released for season four (click here for the full version), fans might worry he’s off the show for good. Those who caught him photographed at the cast and crew’s season 4 kickoff dinner, though, may assume Elam’s back. Exec producer John Wirth confirms it: “He survives the bear attack, but I think you will be surprised to see the manner in which he survives,” he tells EW. “The circumstances of his survival are unique.”

If that—combined with our scoop on Cullen’s relationship with new bride Naomi (now played by MacKenzie Porter)—isn’t enough of a tease for the show’s Aug. 2 return, here’s more from Wirth, including details on the arrival of a few new characters and the episode in which you can expect to see a cameo from Mac Mount, Anson’s rescued French bulldog and social media darling.

Having seen the beginnings of Cheyenne, Wyoming built last season by the show’s production designer, John Blackie, Wirth wanted season four to be set in the town. His first thought was to tell a story about what happens to the guys working on the railroad during the winter. But, unable to film in Alberta during the coldest months, he had to switch gears. “I came up with the idea that maybe somebody would come into Cheyenne to challenge Durant [Colm Meaney] for control of this world,” he says. He took it to the writers’ room, and they learned that there was a man named John Campbell who became the first governor of Wyoming.

“The idea is, he represents civilization. He comes from the East to a lawless place with law and order as his mandate,” Wirth says. “So much of the conflict this year grows out of that sort of knife-edge of civilization meeting frontier: You can imagine the east side of town is civilization, and on the west side of town is the frontier. If you leave town and you had east, you’re gonna get to Chicago or New York; if you leave town and head west, very quickly you’re in the middle of nowhere. What happens when civilization tries to impose itself on an uncivilized frontier?”

Medium‘s Jake Weber plays Campbell (pictured below), whose fictionalized Hell on Wheels backstory has him having been recalled by President Johnson after his efforts helping with the Reconstruction effort in Atlanta got “a little overzealous,” Wirth explains. Cleaning house, president-elect Grant reassigns him to a post in Cheyenne so he can gain control of sly Durant and the town to better facilitate the building of the railroad. “So Grant was kinda killing two birds with one stone: He was cleaning house getting rid of some ‘bad apple’ and putting him out in Wyoming where he was far enough away that if he continued his surly ways, the blowback might not be as much on Grant,” Wirth says. “Campbell is a very unrelenting, unbending, hard-nosed law and order enthusiast. He very much believes that nobody is above the law, with the possible exception of himself and his men, and that if everybody abides by the law, then there will be order in society and things can get done.” Look for Campbell and Bohannon to also have conflict when their paths cross. “The first thing Campbell does is try to co-opt Cullen by offering him a job,” Wirth says, “and Cullen’s attitude is, ‘I’m not gonna work for a carpetbagger.'”

Image zoom Lewis Jacobs/NBC

Also complicating Durant’s life will be Martin Delaney (David Wilson Barnes), who comes in to replace Bohannon as the railroad’s chief engineer. “He’s actually a son-in-law of Sen. Metcalf, the guy who was murdered by Durant,” Wirth says. “He is assigned to the railroad by Credit Mobilier, which is the company that Durant owns. He’s sent out there as a spy. He’s a very capable guy—he’s a war veteran, fought for the North and built railroads back East, but he has no experience building railroads of this magnitude in the wilderness or dealing with somebody as wily as Durant. So I kinda think of him as an order taker,” Wirth says. “If he were in Vietnam and the lieutenant said, ‘Sgt., take your men up that jungle path,’ he would do it, even if they all got slaughtered. Whereas Bohannon would say, ‘F–k you, you go up at that jungle path. I’m not going up that jungle path, you idiot. I’m gonna get a helicopter and fly over it. That’s what I’m gonna do.'”

Episode five will introduce another new face: Jonathan Scarfe playing Sidney Snow, an acquaintance of Cullen’s from the war. “He’s a Southern boy who is on the lam. He takes off on the run from the law and he goes as far West as he can go, which is the end of the railroad,” Wirth says. “He reacquaints himself with Bohannon, and so begins a five or six episode adventure between Cullen and Sidney Snow.”

As for the characters viewers already know:

• The Swede (Christopher Heyerdahl) is still the Swede. “When we left off last season, he was the bishop kind of running this Mormon outpost and had his foot on Cullen’s neck, and that’s certainly where we pick up this season,” Wirth says. “But I will say this about the Swede, as anyone knows who watches the show, he is a bit of a shapeshifter, so you never know how long he’s going to embody any particular incarnation. It’s all up for grabs when it comes to him. I think it’s worth watching to see what happens to him as well this season.”

• There may be hope for fans of Eva (Robin McLeavy). “Eva was left on the outside looking in. Elam’s gone, and she doesn’t know where he is. She gave away the baby, of course. So she’s looking to restart her life and has a tough time of it in the beginning of the season,” Wirth says. “But then she sees a window of opportunity and takes it and changes her circumstances in a surprising way.”

• We’ll see a new side to Mickey (Phil Burke). “Everybody thought that Sean was the one with the brains, and Mickey was the brother that you wanted to go to a party with,” Wirth says. “He reveals himself to be a little more sinister and a little more ambitious than we may have thought he was. And of course, that runs afoul of Campbell when he arrives in town and tries to set up some guidelines for casino gambling.”

• Louise Ellison (Jennifer Ferrin) is running the first daily newspaper in Cheyenne, The Cheyenne Leader. “Her newspaper articles and her covering of the story provides a couple of things: Personal stories for her, but also a larger context that keeps alive the historical context of the series,” Wirth says.

• Both Ruth (Kasha Kropinski) and Psalms (Dohn Norwood) get larger roles. “Psalms used to exist as sort of a sidekick to Elam, and now he’s really grown into his own character,” Wirth says. “Having a church in Cheyenne that’s more of a permanent place of worship changes Ruth’s role in the series a little bit.”

And finally, bonus scoop for anyone who follows Anson Mount on WhoSay or Twitter: Mac will pop up on the show as well. “He appears in episode 403. It is a cameo—he has no dialogue,” Wirth deadpans. (And the reason Mac’s tongue is always out: He’s lost a few teeth, Wirth says. “Ask Anson sometime about Mac’s backstory: It’s a very interesting, kind of heartrending backstory. But he is a really sweet little dog.” And quite happy now, it seems. “Yeah, for sure.”)