Narcos is moving its headquarters and enlisting two new stars to join its ranks.

Michael Pena (Crash, American Hustle) and Diego Luna (Rogue One: A Star Wars Story, Y Tu Mama Tambien) are set to star in the fourth season of the Netflix drug-cartel drama, which will also shift the Colombia-set series to Mexico. Pena and Luna will both be series regulars; details on their characters are being kept under wraps.

Production on season four recently began in Mexico City. Season four will be set in Mexico and will explore the Guadalajara cartel. It will premiere in 2018; a specific return date has not yet been determined.

The first three seasons of Narcos were filmed in Colombia and told a two-season story of Medellin boss Pablo Escobar (played by Wagner Moura) and the cocaine kings who succeeded him, the Cali cartel. The end of the third season, which featured a largely new cast, hinted at Mexico being the show's next backdrop. News of the shift was first reported after a location scout was killed near Mexico City while working on season four.

Netflix on Tuesday confirmed the news, along with debuting a new version of the show's theme song (video below). "Guadalajara is not only the birthplace of mariachi and tequila, it's also the home of the newest season of Narcos. Coming 2018," the streamer posted to the Narcos social media accounts.

Although character details for Pena and Luna are being kept quiet, Narcos is in need of a new leading man on the DEA side as the series continues to focus on its war on drugs. Following Boyd Holbrook's season-two exit, Pedro Pascal took over the starring reins solo with his agent, Javier Pena. The end of season three, however, left Pascal's future with the show open-ended as his character questioned continuing the fight in Mexico. At the time, showrunner Eric Newman warned viewers that the finale scene could be the last for Pascal. "I think you can believe his final words," Newman previously told The Hollywood Reporter. "I think we may do something really interesting that surprises people [next season]. I do think that we've told Pena's story pretty effectively."

On Tuesday, Newman confirmed that the fourth season would no longer be following Pena's story — though he wouldn't rule out an appearance from Pascal. "It was a part of the plan as early as season two," he told THR exclusively of phasing out the show's star. "The design was always to finish out the Colombian story and the players that we’ve come to know there, and then start anew in Mexico."

In addition to a potentially vacant starring role on the "good guy" side, there are also new villains to cast, and one of the early Guadalajara players is none other than the infamous Joaquin "El Chapo" Guzman.

"Chapo was there at the beginning, in a way," Newman had told THR when forecasting his post-Escobar plan for seasons three and four. "He was one of the younger guys in the Guadalajara cartel before it splintered, and he and another guy were given Sinaloa as territory. In our timeline currently, that’s already happened, because that was in 1985. So it depends. If we take our time, it could take a while. If we jump right into it, it could be really soon."

The third season brought the Narcos timeline up to the mid-1990s with the deaths and incarcerations of the four Cali cartel bosses. It is unclear where exactly the fourth season will pick up. Last season introduced Amado Carrillo Fuentes, aka the Lord of the Skies, the nephew of another Guadalajara boss, Ernesto Fonseca Carrillo.

"Past a certain point, and I think we've just reached that point in our show, Mexico became the kings of the cocaine game," Newman said of the third season's passing of the torch. "You realize that you shut down the Miami-Caribbean corridor, where they were bringing all their cocaine in for years, and that cocaine is going to find another way in. Why not this country of 130 million people with a 2,000-mile border they share with us? That seems to make the most sense, and that's exactly what happened." The Guadalajara cartel was the first Mexican drug trafficking group to work with the Colombian bosses in the cocaine trade.

Pena's credits include Crash, The Martian and American Hustle, along with a starring role in the biopic Cesar Chavez. He most recently appeared alongside Dax Shepard in the CHiPs remake and will next star in the upcoming post-9/11 war drama 12 Strong. On the TV side, the actor previously starred in The Shield and Eastbound & Down. Pena is repped by CAA, Management 360 and attorney Rick Genow.

Luna had a breakout role in last year's Rogue One and most recently starred in the Flatliners remake. The actor, director and Mexico-born producer has appeared in films such as Milk, The Book of Life and Y Tu Mama Tambien after getting his TV start in telenovelas. He and Gael Garcia Bernal own Canana Films, and the Pena-starring Cesar Chavez marked his English-language directorial debut. Luna is repped by WME and Hirsch Wallerstein Hayum Matlof and Fishman.

Newman, Jose Padilha, Doug Miro and Carlo Bernard executive produce Narcos, which is is produced by Gaumont Television for Netflix.