Borrower of the Night by Elizabeth Peters is a story about Vicki Bliss, a extremely beautiful woman who is also brilliant and self reliant. Vicki and her friend Tony are reading and find clues that hint at what happened to an art piece that some believe to be a myth. Vicki and Tony head to Germany to find the piece but soon discover they are not the only ones after the relic. Things become quickly dangerous as it seems a ghost haunts the castle where Vicki and Tony are staying and conducting their research. The desire for the relic drives people to desperate measures and Vicki and Tony are nearly killed, along with others in the story, before the art piece is found and returned to its rightful owner.

Vicki Bliss is a professor at a small college with her friend Tony. Although she likes Tony and he has asked her several times, Vicki refuses to marry him explaining that it is nothing more than a way for a woman to be controlled. Tony decides he will challenge Vicki in order to prove that she is not superior to him intellectually. If Tony wins then Vicki will have to marry him. Vicki and Tony stumble upon clues referring to a piece of art made by a famous sculptor and Tony and Vicki decide that this will be their goal and the first one to find the sculpture wins. An old rival of Tony's, George Nolan, joins the chase and the three of them head off to Germany to stay at the Drachenstein castle where the sculpture is most likely hidden.

Once Vicki reaches the castle she and Tony find that there are other suspicious characters there, including the owner of the castle, Irma Drachenstein, and her seemingly cruel aunt. Vicki and Tony start snooping around the castle and are able to find small clues around the castle that refer to the mysterious sculpture. Vicki and Tony are out walking when they see what they believe is the long dead Konstanze who was burned at the stake for being a witch.

Vicki and Tony, as well as other people in the castle are attacked throughout the story. Vicki happens to find a compartment and realizes that Konstanze poisoned her husband and hid the sculpture but then was burned for being a witch before she could retrieve her prize. Vicki, Tony and another guest at the castle are moments from getting the sculpture when they are attacked and locked in a airtight room at the bottom of the castle. Vicki and the others barely get out in time to see George Nolan carrying an unconscious Irma to the top of a building to throw her off. They are able to slow George down and before he can finish killing Irma she awakens and pushes George to his death. Vicki confronts Irma's aunt who stood to gain Irma's fortune if Irma died and the aunt quietly slips away. Vicki is able to retrieve the sculpture and gives it to Irma who plans to put it in a museum. Vicki and Tony end in a stalemate and Vicki says that she does not ever intend to get married.