梅勒尼(玛丽-凯特·奥尔森 饰)和艾丽(艾什丽·奥尔森 饰)是一对13岁的双胞胎,她们心地善良,聪明可爱,但性情不羁,对未来有着自己的打算和想法。在学校里两人功课学得很好,但是她们更渴望可以学到更多书本上没有的知识,比如如何与人相处。
Based on the novel by Karel Capek, the prominent Czech writer of the early 20th century who coined the word robot for his play R.U.R., the story revolves around a discovery of Krakatit - a powerful explosive - by Prokop, an experimental scientist who, following an accidental explosion in his lab, slips in and out of delirium. When he realises that, in a delirious period, he has given the formula for making Krakatit to one of his colleagues, he tries to find the man, who does not realize how dangerous a thing Krakatit is. In the process, he nearly gives his discovery away again to foreign interests, a group of anarchists, and even greater forces of darkness...