Lindy Booth's character on TNT’s upcoming series The Librarians isn’t a typical television role. Cassandra Cillian suffers from an extreme case of synesthesia, a rare neurological condition that leads to peculiar sensory experiences.

“I describe it as having a fun house sort of inside your head,” Booth told Enstars. “It’s all very, very overwhelming to her and she can’t control it in the beginning.”

The condition has forced Cassandra to live her life feeling insecure and withdrawn from others. That all changes, however, when she comes to the Metropolitan Public Library and meets Flynn Carsen (Noah Wyle), who helps Cassandra see that what she has is far from a setback. It becomes easy for her to get along with Flynn and the rest of the team - Eve Baird (Rebecca Romijn), Ezekiel Jones (John Kim) and Jacob Stone (Christian Kane) - as they try to save Earth’s magical treasures.

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“It’s the first time anyone’s ever told her this and so, for Cassandra, this whole thing is a journey of going from seeing life as a curse to seeing it as a gift,” Booth said. “There’s an incredible joy that she finds in having a new shot at life.”

Cassandra is also a math and science expert, something Booth admits she’s not. In order to get a better grasp of what her character was talking about, the 35-year-old said she spent hours studying topics like dimensional geometry.

“I remember turning to Christian Kane one day and just being like, ‘It is so hard playing someone so much smarter than you,’ and he was like, ‘You’re telling me! I have no idea what I’m talking about!’” the Toronto native recalled.

Although her character was a challenge, Booth said she feels “blessed” for the opportunity to play Cassandra and anticipates fans delving into the magical world.

“I feel like we spent all this time working on it and I love it so much,” Booth said. “I’m just so excited.”

The Librarians premieres Sunday at 8:00 p.m. EST on TNT.

Watch the trailer below: