Tom Ellis may have let slip that Tricia Helfer is returning as mum in "Lucifer" Season 5. After which, he also revealed that the upcoming final season will be split into two.

ET correspondent Katie Krause dropped by the set of the show while the cast was filming Episode 4. She had a chat with some of the stars including Ellis, who plays the titular character. During the interview, Krause name dropped Helfer, to which the Welsh actor replied "mum."

"I do wanna quickly ask you about Tricia Helfer coming back," Krause asked, and Ellis smiled as he replied, "Mum."

"Is it mum though?" Krause said, and the actor threw back the question at her and played safe with his next response.

"Is it mum, is it Charlotte? I'm just gonna leave it out there. Is it mum, is it Charlotte? " he said. Ellis revealed that Helfer's character is a big part of the story Season 5 is going to tell.

Helfer played two characters in the show. She was Lucifer and Amenadiel's mother in the body of a human. That human is Charlotte Richards. However, she looks nothing like her old self in her promotional photo for "Lucifer" Season 5.

The Season 4 finale saw Lucifer returning to Hell, leaving Chloe Decker (Lauren German) behind after she confessed that she loves him. The final scene saw the devil back on his throne and it is unclear if or when he will reunite with Chloe on Earth.

Ellis did not say anything when asked when fans can see Lucifer back on Earth. He just gave a tease and said that it will be tackled on early in the season. He said that fans will "find out a lot of stuff in the first episode about what Lucifer's intentions are."

"Lucifer" Season 5 is going to be 16 episodes long and for this reason, Netflix has decided to split the show into two halves. Ellis made this announcement during Kelly Clarkson's set visit.

"Netflix is gonna drop eight episodes and then there's gonna be a little break and they're gonna drop another eight episodes," he said.

Splitting shows into two halves is nothing new for Netflix. According to TV Line, it has been their go-to-move for longer shows. They have done the same with "BoJack Horseman," "Unbreakable Kimmy Schmidt," and "Fuller House." This not only gives the cast, writers, and showrunners time to do some revisions but it also heightens the excitement.

Tom Ellis returns as Lucifer Morningstar in the Netflix series "Lucifer." Lucifer/Fox