original: Witnessing the murder of his colleague Owen, Jack shoots his killer in the forehead, killing him in an act of swift revenge.
simplifications: Jack saw his partner killed, so he shot the killer in the forehead out of revenge. Jack shoots Owen's killer in the head, killing him in revenge. Jack shoots Owen's killer in the forehead. It was an act of revenge. Seeing the murder of his colleague Owen, Jack shoots his killer in the forehead in revenge. Seeing the murder of his colleague Owen, Jack shoots his killer in the forehead. He killed him in quick revenge. After seeing Owen get killed, Jack shoots and kills the killer as revenge. Jack witnessed the murder of his colleague Owen. Later Jack shoots his killer in the forehead in revenge. Seeing the murder of his coworker Owen, Jack shot the killer in the head in a swift act of revenge. Jack saw his colleague Owen being murdered. Jack shot Owen's killer in the forehead in an act of quick revenge. Witnessing the murder of his coworker Owen, Jack shoots his assassin in the forehead, killing him in an act of swift revenge.