THE fourth season of “Better Call Saul” will feature some familiar faces and a mystery character from the world of Walter White.

Executive producers Vince Gilligan and Melissa Bernstein on Wednesday teased the show’s forthcoming “Breaking Bad” crossover at the AMC Summit in New York.

“Season 4 is so good,” Gilligan told the media during a panel. “It gets darker, it gets richer. It’s still got funny in it, but on the Venn diagram of ‘Breaking Bad’ and ‘Better Call Saul,’ the overlap in the center is getting bigger.”

The producer, who co-created the “Breaking Bad” prequel with Peter Gould, continued: “There is a very important character. I’m not promising you ever saw this character, but there was a very important character nonetheless from the ‘Breaking Bad’ era who we’re going to meet this year. You’re going to be impressed with him.”

Bernstein confirmed that the character Gilligan was referring to is Lalo, a person who was named on “Breaking Bad” but who never appeared onscreen. Lalo was mentioned in the first scene with Saul Goodman (Bob Odenkirk) during “Breaking Bad” in the Season 2 episode aptly titled “Better Call Saul.”

“Other than Lalo, we have a couple of new characters that we’ll be reintroducing to the world,” she added. “We probably don’t want to say who yet, just to preserve the fun of that for the fans.”

“Better Call Saul” stars “Breaking Bad” alums Jonathan Banks and Giancarlo Esposito.(SD-Agencies)