Henry DeTamble: The male protagonist, Henry, is a librarian who involuntarily travels through time. His time-traveling condition causes him to experience life out of sequence, complicating his relationships and personal life.

Clare Abshire: The female protagonist, Clare, is an artist who meets Henry when she is a child and he is an adult. As Henry’s time travel affects their relationship, Clare’s unwavering love and patience are central to the story.

Gomez: A friend of Clare and Henry, Gomez has a complicated relationship with the couple. He harbors unrequited feelings for Clare but remains a loyal friend.

Charisse: Gomez’s wife and Clare’s best friend, Charisse is supportive of Clare and Henry, even as she navigates her own relationship challenges with Gomez.

Alba DeTamble: The daughter of Henry and Clare, Alba inherits her father’s time-traveling abilities. She plays a significant role in the later parts of the story, representing a new generation dealing with time travel.

Dr. David Kendrick: A geneticist who becomes involved in Henry’s life, Dr. Kendrick studies Henry’s condition in an attempt to understand and potentially mitigate the effects of time travel.

Ingrid Carmichel: Henry’s ex-girlfriend, whose relationship with Henry ends tragically. Ingrid’s presence in the story highlights the difficulties Henry faces due to his uncontrollable time travel.

Kimy Goldstein: A close friend of Henry’s family, Kimy provides emotional support and helps take care of Henry during his frequent absences caused by time travel.

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