剧情描述一家研究DNA遗传工程的药厂实验室将小精灵加以实验，结果制造了一群破坏力强烈的怪物，将大楼搞得人仰马翻，男女主角费尽九牛二虎之力才把这群怪物消灭。

When FBI Agent Zack Stewart is killed, Agent John Ripley takes over the three cases he was working on, hoping one will lead to his killer. The first involves gangster Joe Walpo and Ripley finds his hideout through Joe's girl friend, Connie Anderson. Joe is killed but it is established he was 400 miles away when Stewart was murdered. The next involves a car-theft gang which Ripley breaks up by using one of the gang, Vince Angelino and his wife Julie. The last case involves Kate Martell, the victim of an extortionist who threatens to kidnap her child unless she pays him $10,000

Scientists and American Air Force officials fend off a blood-thirsty alien organism while at a remote arctic outpost

三年后，科学家韦恩·斯萨林斯基（里克·莫拉尼斯Rick Moranis饰）一家人搬到内华达州的滨海社区，继续他的电磁分子研究。三年前，他曾经因为操作不当把孩子们的身体“缩小”了，闹出了一连串啼笑皆非的故事。而这次，糊涂韦恩仍旧重蹈覆辙，大摆乌龙。在一次实验过程中，只有两岁的小儿子亚当，居然被“变大”了。小亚当只要一接触电流，身体就会不停的长大。一家人展开了挽救行动，可这根本跟不上小亚当的变大速度。转眼间，小亚当已经长成足有3500公分的巨婴。而更麻烦的是，小亚当居然跑上了街头，朝着赌城拉斯维加斯走去，于是他的奇妙大冒险就这样开始了。　　小亚当能否缩小回正常婴儿的大小，乌龙科学家韦恩又是否能再次摆脱囧境，一家团聚呢？

一场在极圈进行的原子弹爆炸实验，释放了冰层中沈睡一亿四千年的恐龙，这只恐龙跑到纽约市大肆侵略，造成巨大恐慌。