We never talk to strangers on the train. That is the rule. But what would happen if we broke it?

Every morning at 8:05, Iona Iverson takes the train to work. Every day, she sees the same people and makes guesses about them – she even gives them nicknames. But they never talk. Obviously.

Then, one morning, Smart-but-sexist Surbiton chokes on a grape in front of Iona's eyes. When another passenger intervenes and saves his life, a chain reaction is set off. A diverse group of people with only the commonality of taking the same train learn that the assumptions we make about others do not align with reality. But when Iona's life starts to go downhill, will these new friends come to her aid?