Who is the true Colin? Why do you think he wants to time travel so badly? Do you think it's Colin that arrives in World War II England in the last chapter of the book? Do you think he has anything to do with the drop locations not working?

Discuss the relationship between Polly and Colin. Are they friends, foes, in love, or colleagues? How does their relationship change throughout different points of the novel? Why do you think Colin wants to help Polly with her research? Is there true competition in their relationship? How does Polly feel about Colin? How does Colin feel about Polly? Why do think Colin reveals his feelings to Polly?

Discuss the relationship between Eileen and the Hodbins. Is Eileen just caring for them or does she truly care about what happens to them? Is there true competition in...