A winter's evening and a trio of unruly youths board a bus and gang up on teenager Luke Donnelly, hurling abuse and threatening to kill him. The bus is full but no one intervenes until Jason Barnes, a young student, challenges the youths. Luke seizes the chance to run off the bus but his attackers follow.Andrew Barnes is dragged from the shower by his wife Valerie: there's a fight in the front garden and Jason's trying to break it up. Andrew rushes to help and the assailants flee. Jason shouts to his father to phone an ambulance - Luke is badly hurt. Minutes later Jason collapses in their living room, he has been stabbed. The blow proves fatal.Valerie and Andrew are devastated by the loss of their only child, and react in very different ways to their grief. Valerie wants justice, revenge even, but Andrew is desperate to find some meaning in Jason's sacrifice. Luke survived the assault thanks to Jason's actions, but is in a coma.As his marriage disintegrates, Andrew secretly visits Luke and his mother Louise and a fragile friendship develops. Meanwhile the press begin to paint a picture of Luke as a less than innocent victim and raise questions about the cost of Jason's heroism.One of the offenders confesses to the attacks and shows remorse while the others plead not guilty. Conflicting accounts emerge during the trial. With some parties prepared to lie, the matter of uncovering what really happened is far from straightforward, and the jury's verdict hard to predict. A novel that explores the issue of whether to intervene or look the other way and the fall-out from either decision.Split Secondtackles questions of bravery, fear and kindness and depicts the human impact of violent crime.