While driving through the desert with his wife Carol Marvin to a military base to send the eleventh rocket to the orbit of Earth for helping the exploration of the outer space in the Operation Sky Hook, Dr. Russell A. Marvin and Carol see a flying saucer and accidentally records a message in their tape recorder. Once in the base, Dr. Russell is informed by his father-in-law and general that the ten first satellites had mysteriously felt on Earth. When Dr. Russell decodes the message, he encounters the aliens that ask him to schedule a meeting with the leaders of Earth in Washington in 56 days with the intention to invade Earth without panicking the population. Dr. Russell develops an anti-magnetic weapon that becomes that last hope of human race against the hostile aliens. 　　译文(2): 在“天钩行动”中，拉塞尔 · A · 马文博士与妻子卡罗尔 · 马文驾车穿越沙漠，前往一个军事基地，将第十一枚火箭送入地球轨道，以帮助探索外层空间时，他们看到了一个飞碟，不小心在录音机里录下了一条信息。一进入基地，罗素博士就被他的岳父和将军告知，第一批十颗卫星已经神秘地探测到了地球。当罗素博士解码信息时，他遇到了外星人，他们要求他安排56天后在华盛顿与地球领导人会面，目的是在不惊动民众的情况下入侵地球。罗素博士研发了一种反磁武器成为人类对抗敌对外星人的最后希望。