John’s married mistress who travels with him to London. Initially dismissive of being followed, she is later revealed to have been shot and killed in the subsequent train collision. Her death and the recovered documents drive the central mystery and John’s psychological unraveling.
Waterson treats Susan as a primary victim in his official crash inquiry.
John and Susan share a clandestine romantic relationship that drives the initial plot forward.
Explore the full interactive character relationship map of The Interrupted Journey