Here’s how The Librarians’ Cassandra’s had her brain tumor removed in season 3 episode “And The Eternal Question.” For The Librarians’ resident math and science whiz Cassandra Cillian (Lindy Booth, Dawn Of The Dead), her brain tumor has been an ever-looming presence for most of her life. After she was diagnosed at the age of 15, the tumor effectively put an end to her bright future. However, while her tumor was a ticking time bomb, it also caused synesthesia as a side-effect which significantly enhanced her flair for math and science. Subsequently, Cassandra was wary of what having the tumor removed might do to her abilities.

Nevertheless, Cassandra’s tumor was slowly killing her and during the first season of The Librarians she hoped to use magic to cure herself. This led a misguided Cassandra to double-cross her fellow Librarians by colluding with Dulaque (Matt Frewer), Lamia (Lesley-Ann Brandt) and the rest of the Serpent Brotherhood. Although her actions were understandable, Cassandra betraying the trust of the other Librarians was something that took time to repair.

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In “And The Eternal Question,” Cassandra was given another chance to beat her tumor by way of magic. Early on in the episode, Cassandra was told by a doctor she needed to have surgery on her tumor immediately but refused, still worried its removal would impede her abilities. Instead, she dove into the Librarians’ latest mission - investigating a mysterious holistic spa linked to a death by spontaneous combustion.

The Librarians Clara Lago Lindy Booth

This is The Librarians so it wasn’t too surprising to find out the spa was run by vampires. One of those spa vamps – a benevolent bloodsucker named Estrella (Clara Lago, The Commuter) – formed a connection with Cassandra and offered her a way out of her terminal diagnosis by giving her vampiric immortality. It soon turned out Cassandra didn’t need Estrella’s gift of immortality after she collapsed and was rushed to the hospital for emergency surgery on her tumor.

Incredibly, the surgery was successful but Cassie found she was initially unable to use her abilities after coming around. However, after doubting her future as a Librarian, Cassandra’s powers returned even stronger and gave her a new ability to communicate telepathically too. It turned out Cassandra’s tumor was hindering rather than causing her abilities. After “And The Eternal Question” Cassandra was able to carry on without the specter of death hanging over her and soon discovered her newfound powers would prove useful in later episodes of The Librarians.

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