All good things must come to an end, even "Scandal".

In an interview with NPR, the show's creator Shonda Rhimes said she knows how and when the hit show's story will conclude.

"I feel like there is a finite amount of Scandal to be told," Rhimes admitted in a recent interview with NPR. "So I know what the end of Scandal will be, and I feel really good about that. And I can see where the end point is. And I don't think I'm going to change that. ... I know how long I think it will be. But we'll see." 

Rhimes said the casting of Olivia Pope's character, played by Kerry Washington, was in fact driven by some very specific ideas about the character.

"There were certain things about that job ... there were ways in which she [might] be treated that I thought were very specific to the black experience," Rhimes said. "We did an episode where she walks into the room, and the client immediately assumes that Abby the tall, white redhead she works with is Olivia Pope."

The writer/producer said "Scandal" is a different kind of show and has a set expiration. The show has recently cast Khandi Alexander as Olivia Pope's mother. The 56-year-old actress made her first appearance, as Maya Lewis, on Thursday in a series of flashbacks. 

Rhimes also mentioned the end of "Grey's Anatomy," which she said she's planned and then had to plan again because the show keeps going and she's still interested in the characters. The ABC hit show is currently in its 10th season.

"I knew the end of Grey's Anatomy, and then we kept going, so that I finally just had to write that and move past it," Rhimes said. "Who knows, at this point, how long that show's going to go? It's going to go as long as I feel interested in what happens to those characters."

"Scandal" airs Thursdays, 10 p.m. EST on ABC.