Shantel VanSanten was just a short replacement for Missy Peregrym who was on maternity leave. Now that Missy is back, Shantel has to leave the show. However, she can be back again in the future.

The actress was added to the team as a substitute for a fellow actress Missy Peregrym, who took leave from her job for the birth of her second child. Missy will be returning to the series, so the actress, Shantel is being written back from the series. It seems that her character is not permanently disposed of but is put off while there is the re-entry of the actress, Missy, in the show.

The show creator explains that it was always the intention of keeping the actress for ten episodes while Missy was having her kids and recovering. The plan was to bring her back after her maternity leave. 

The showrunner and the executive producer, Eid keep hopes alive regarding Nina's appearance on the show. He did not have to kill off her character as she was an incredible addition to the show and her relationship with Scola will help him keep her character alive. He says that she is not gone for good and we will be able to see her soon. 

She plays Nina Chase, a secret undercover agent who falls in love with Scola. 

In the episode Double Blind, Episode Six of the latest season of FBI, Nina finds out that she is pregnant and chooses to take a break from the threatening and unstable world of being an undercover agent. She decides to leave her team and explains that she is going to take a desk job which is more secure, and tries to see what the future holds for her. 

Scola, the father of her child and her lover is shocked when she tells her all this and especially when she states that she needs some time. After her exit, for the time being, the cast and crew of the FBI are ready to welcome Missy, who plays the character of Maggie Bell.

The actress stated that she is curious to explore where the situation will lead with the character of Nina. As the fourth season of For All Mankind needed to be produced, she was working on different characters simultaneously. She is happy and thankful that her character, which was supposed to be minor developed into a more significant role.