Rachel sees the same couple breakfasting on their deck each morning as she passes by in her commuter train. She thinks their life looks perfect until, one day, she sees something shocking. The train moves on immediately, but she can't keep it to herself and informs the police. Has she done more harm than good?

When Captain Colter Stevens wakes up in the body of an unknown man, he discovers he's part of an experimental government program called the 'Source Code' that enables him to cross over into another man's identity in the last eight minutes of his life. Armed with the task of identifying the bomber of a Chicago commuter train, Colter must relive the incident over and over again, gathering clues until he can solve the mystery and prevent an even deadlier...

"A cryptic murder pulls a former soldier turned financial analyst deep into the corruption and menace that prowl beneath the opulent world of finance"-- "Every day without fail, Travis Devine puts on a cheap suit, grabs his faux-leather briefcase, and boards the 6:20 commuter train to Manhattan, where he works as an entry-level analyst at the city's most prestigious investment firm. In the mornings, he gazes out the train window at the lavish homes...

Rachel is unemployed and devastated by a recent divorce. She fills her time with drinking, riding the commuter train, and fantasizing about a seemingly perfect couple the train passes by every day. Then one morning, Rachel sees something shocking that unravels her and entangles her in an unfolding mystery.