In the Season 4 finale, the world morphs into a horrible and unrecognizable place—one where the Library never existed—and it's up to Baird to bring the Librarians together before the bleak, knowledge-less world becomes the new reality.
It's time to choose the singular Librarian to tether with Baird, but no one can decide so the Library takes it upon itself to help. Reducing the Librarians to their most primal selves and abandoning them in a landscape of their own nightmares, it's The Trial of the One.
When Jenkins body-switches with a 28-year-old slacker named Jeff, he must find his way back into the Library to correct the mistake. But he will need a team to do it, and enlists the help of Jeff's hapless Dungeons & Dragons friends.
After Cassandra freezes up during a mission, she decides it's past time to go on a vacation. Searching for her ideal town, she lands on Havenport, the "Safest Town in America." At first blush, it seems just what she needed.
When Baird goes after Nicole Noone in an attempt to repair her rift with the Library, she ends up joining Nicole in a mission to retrieve a dangerous artifact before it falls into the hands of Russian grave robbers.
A Librarian from the past teams up with the Librarians of the present to take down an ancient and powerful enemy let loose in the modern day. When superfan Flynn is met with the prospect of teaming with his Librarian hero Darrington Dare, he could not be more excited, until Darrington leaves the Librarians with this dire warning: There can be only one Librarian - ignore at your own peril.
When Flynn and Baird are sucked into Baird's favorite classic film noir movie, the Librarians will need to perfect their lassoing skills, sharpshooting, and snappy dialogue if they're going to make it out alive.
When Santa takes Flynn, Baird and Jenkins on his first vacation in centuries, he leaves his beloved sleigh in the care of the Librarians. But when Ezekiel's career criminal mother steals the magic door, they must use the sleigh to save her, as well as Christmas itself, from Santa's Grinch of a brother, the Patron Saint of Thieves.
When people begin getting hurt in the unluckiest of ways, the Librarians are led to a casino where the owner appears to possess an artifact capable of stealing people's luck. Despite falling under the bad luck curse themselves, the Librarians must turn the tables before the plague of bad fortune spreads to the wider world.
When a secret sect of the Vatican Church unearths an ancient map detailing the locations of the four cornerstones of the Library of Alexandria (the original Library), it's up to Flynn and the Librarians—with the help of an unexpected ally—to stop them before the stones can be used to destroy the Library. The Season 4 premiere.