When Alex returns home, he is told by Alan Blunt that the mission was a success, that all of the boys were rescued and all fifteen clones were disposed of. Alex is then called to his school, where he discovers that the sixteenth clone, who Grief’s surgeons had surgically altered to resemble Alex, eluded capture. The clone plans to kill Alex in revenge for killing his “father”, Dr. Grief. Alex and the Grief clone fight on the school roof, and the science department catches fire. As the two boys fight, one of them (presumably the clone) falls to his death. The other walks away.