25 years have passed, and old McCreedy rots away in a mental hospital, raving about demonic creatures. Meanwhile, Kevin and his friends, now all grown up but not all that much wiser, are visited by a bunch of wish-fulfilling monsters.

美国政府秘密研制的生物武器,巨型蜘蛛"母锁",在联邦号航天飞机上进行注入外星人DNA试验的时候遭遇太阳风暴,发生事故。航天飞机坠毁在地球,"母锁"在很短的时间内变异为高达9米的巨型蜘蛛,四处攻击人类。政府官员玛费和大学生记者马西冲破政府想要隐瞒事实的重重阻挠,不仅向公众披露了政府的所作所为,而且成功地消灭了为害人间的巨型蜘蛛。