To protect his books, Albert, the young librarian, must put his prejudice aside and make friends with a bat.
Albert, a young librarian discovers one day that a bat is living in his dear library. Afraid for his books, he decides to get rid of her. Little does he know that Eugénie the bat used to protect the library against the book feeding insects.... Now that the bat is gone, the books are left unprotected and the bugs can eat them without being disturbed. The librarian needs to find a solution because the insects have already destroyed many books... But the bugs are everywhere, he can't do anything.