The characters of Doomsday Book by Connie Willis are as follows:

• Kivrin Engle is a female medieval historian at Oxford who requests Professor Dunworthy to allow her to time travel back to 14th century Oxford for research.

• Professor James Dunworthy is an Oxford professor of medieval history and Kivrin's mentor.

• Doctor Mary Ahrens, a friend of Professor Dunworthy, dies trying to save others from a modern influenza epidemic in 21st century Oxford.

• Colin is a friend of Professor Dunworthy, and his friend Mary's grand-nephew.

• Professor Gilchrist is in charge of the time travel project. He orders the time travel net closed to prevent the transmission of the plague from the 14th century to the present, stranding Kivrin in the process.

• Badri Chaudhuri is the technician that sets time travel coordinates. He comes down with influenza and sets the coordinates incorrectly, landing Kivrin in the wrong time period (during the Black Death) in medieval Oxford.

• Gawyn is a woman in medieval Oxford who supposedly found Kivrin and took her to the local manor.

• Agnes and Rosemund are children Kivrin befriends as she integrated into medieval Oxford society.

• Father Roche heads the local parish congregation. He sees Kivrin materializing from time travel and concludes she is a messenger sent to him and his congregation by God to help them.