Doomsday Book, by Connie Willis

Rating: 4
Pages: 578
Awards: 1993 Hugo, 1992 Nebula

The trickiest part of writing believable time travel stories is handling the paradox problem: what happens if I go back in time and prevent Kennedy's assassination? In Doomsday Book, Connie Willis solves the problem by making it impossible to change the past. Past events are fixed, and the laws of the universe don't allow them to be changed. If I try to travel back in time to prevent the Kennedy assassination, my arrival time will "slip" past the critical juncture, and I will arrive too late to prevent the historical events from occurring.

This makes time travel difficult, because you can never know exactly how much slippage there will be; slippage can be as little as a few seconds or as much as several years, depending on the events at your target destination time.

Doomsday Book begins as Kivrin, a graduate student, is sent back alone to a village in 1320 to study conditions in England in the Middle Ages. She is eager but ill-prepared; her trip is part of a petty university departmental power struggle, by professors who care more about their standing than the wellbeing of their students.

Kivrin arrives in the Middle Ages and immediately falls ill. Back in the 21st century, a similar outbreak of illness occurs. The diseases seem similar, but the 21st century influenza is contagious and deadly, but back in the Middle Ages, Kivrin is the only one sick. But no sooner does Kivrin recover from her illness than another sickness strikes the village; Kivran watches as everyone in the village falls ill and dies horribly.

The majority of the book is an exercise in contrasts between the way 21st century and 14th century England deal with epidemics. Kivrin's story is heartrending, and makes Doomsday Book worth reading. The 21st century epidemic feels like a farce, though, and is hard to take seriously. In fact, everything about the 21st century seems petty and unreal; it's not a convincing future. But Connie Willis has created a captivating 14th century, and that's why Doomsday Book rates a four.