The 15:17 to Paris is based on the true story of Anthony Sadler, Alek Skarlatos and Spencer Stone, three Americans who thwarted a terrorist attack on a train traveling from Brussels to Paris,
David Haller was diagnosed as schizophrenic at a young age and has been a patient in various psychiatric hospitals since. After Haller has an encounter with a fellow psychiatric patient, he is confronted with the possibility that there may be more to him than mental illness.