Plot

A high school prodigy builds an atomic bomb with stolen plutonium to win the 45th National Science Fair and expose a nuclear weapons lab posing as a nuclear medical research facility in Ithaca, NY.

Paul Stephens, a high school student in Ithaca, New York, is generally unmotivated academically despite being a science geek, his interest, as per his age, mostly in those science items that have a wow factor. It is his interest in science that connects him to Dr. John Mathewson, a scientist recently having relocated to Ithaca and who is interested romantically in Paul's soon to be divorced mother, Elizabeth Stephens. It is in that want to impress Elizabeth through Paul that John invites Paul to Medatomics, a medical research facility, so that he can demonstrate some of those "wow" type experiments on which he and his colleagues are working. While impressed enough, Paul is nonetheless more interested in something else in the facility that John only makes passing reference to when asked, that "green goo" which in combination with other things Paul discovers around the facility making him believe that the facility really a secret government nuclear one, the green goo radioactive material for atomic bombs. Paul and his classmate/girlfriend Jenny Anderman, an aspiring journalist, want to expose Medatomics for what they believe it to be as there was no community notification about operating a potentially dangerous nuclear facility there. While Jenny wants to go the traditional route in writing an exposé, Paul believes there is only one effective way to get their message across to the world while making them both famous. The further Paul, with Jenny's help, gets to enacting his plan to its intended end, the more he may place their lives and that of the community in danger, especially if the authorities discover what he is doing.—Huggo

The Manhattan Project tells of how 17 year-old Paul Stephens (Christopher Collet) and his girlfriend Jenny Anderman (Cynthia Nixon) an aspiring journalist, wants to alert their community a secret nuclear facility in their hometown of Ithaca, NY. While Dr John Mathewson (John Lithgow), supposedly a doctor in this "pharmaceutical research plant," the very same facility in reality a nuclear plant, becomes involved romatically with the Paul's mother Elizabeth (Jill Eikenberry) and friends with Paul. While Dr Mathewson is visiting Paul and Jenny steal the plutonium and construct their own atomic bomb for a science fair in New York city. The movie is funny, and at times, frightening, showing how what can really happen if a teenage genius, finding all things possible on the internet, in published books, and unclassified government papers, can really build himself a nuclear bomb, all for a first place or first prize in a science fair.