NBC is looking at a possible spinoff to "The Blacklist," which, if greenlit, will be starring Famke Janssen.

There's no word yet on what story the spinoff will follow but it will center around Janssen playing Susan "Scottie" Halsted, who appears to be Tom's mother in the original series. The character will be introduced in "The Blacklist's" episode 321 airing on May 5. To gauge the feasibility of the spinoff, NBC will be airing a backdoor pilot on May 12, a week before "The Blacklist's" season three finale.

Janssen has played Jean Grey in the "X-Men" movies and "The Wolverine;" Ava Moore in "Nip/Tuck;" Olivia Godfrey in "Hemlock Grove;" and Eve Rothlo in "How to Get Away with Murder."

Michael Dinner has been tapped to direct the backdoor pilot but no details have been released as to who will be writing for the episode. If the spinoff does go into production, it will also star Edi Gathegi, who has a recurring role on the flagship as Matias Solomon, a Cabal operative tasked with hunting down Raymond Reddington.

According to sources, more casting information will be made available soon and that the spinoff may be home as well to some familiar faces from the flagship.

It is also not clear if the spinoff will be making it to the network's 2016-2017 broadcast season, if it does move forward. If it does, it will bring to 22 the total number of pilots NBC is working on.

Like "The Blacklist," the spinoff will be produced by Davis Entertainment and Sony Pictures Television. It will also have Michael Watkins and John Fox ("The X-Files"), John Davis ("Predator"), John Eisendrath ("Alias") and Jon Bokenkamp ("The Call") as executive producers.

"The Blacklist" remains to be one of NBC's biggest draws, averaging an audience of almost 12 million every week. It has been renewed for a fourth season.