Harry S. Stamper is the griity, roughneck but genius oil driller, who is a man known to never miss his mark. He is chosen by NASA to drill a hole on an asteroid headed for Earth. He leads a ragtag team of expert drillers who may have questionable pasts, however all are devoted and extremely loyal to him. He detests A.J, who really is an image of what he used to be around the same age, and he is furious with A.J upon discovering that his daughter, Grace, is in love with him (he feels she can do better).Stamper is in no way a fool, nor ignorant. His crew respects him, his daughter loves him (despite him being afflicted with what she calls a natural immaturity) and the members of NASA, although intially judging him incorrectly, grow to understand why. Harry is a man who defines responsibility, aware that ever decision he makes and how it can affect those around him. Eventually this lesson is passed on to A.J. Truman realizes that when Stamper says he'll make the mark, he knows it will happen. Col. Sharp believes him and even goes against orders to allow Stamper to succeed in the mission. Because of Stampers perserverence, the mission is accomplished, although at the cost of his own life. A.J had drawn the lot to set off the detonator when the delay switch was damaged, Harry tricks him, sabotages A.J's spacesuit and sends him back to the ship, in order to spare his life.His decision to sacrifice himself in place of A.J was done for two reasons, 1. He wanted to be sure the job was done right and 2.He knew Grace would be destroyed if A.J died. Stamper and his crew did succeed and the end of the movie it is acknowledged that A.J will take care of Grace, now that her father is gone.Stamper is a diplomatic man, however he can have moments of rage-shown when he is chasing A.J with the shotgun after catching him in bed with Grace. All in all, a deeply loyal and patriotic man, he is an excellent everyman, who stands by his integrity and his morals. Show less «