Chain Reaction is a 1996 American science fiction action thriller film directed by Andrew Davis and starring Keanu Reeves, Morgan Freeman, Rachel Weisz, Fred Ward, Kevin Dunn and Brian Cox.

The plot centers on the invention of a new non-contaminating power source based on hydrogen and the attempts by the United States Government to prevent the spreading of this technology to other countries.

While working with a team from the University of Chicago on a project to convert hydrogen from water into clean energy, student machinist Eddie Kasalivich inadvertently discovers a sound frequency in his home laboratory that perfectly stabilizes their process the next day.

Back in the laboratory, Alistair and assistant Dr. Lu Chen prepare to upload their discovery to the Internet to share the breakthrough with the world, while a van approaches the premises.

Once he has dropped Lily off at Alistair's house, where she lives on the third floor, Eddie returns to the laboratory to retrieve his motorcycle but notices a suspicious van departing.

After tracing the license plate on the thugs' van, Eddie tracks them to the secret C-Systems Research facility where Paul and Lyman are forcing Lily and Chen to replicate the project.

When C-Systems' test reactor malfunctions, Paul, the scientists and the prisoners all depart, allowing Eddie to furtively "fix" the system that night.

Lyman responds by shooting Chen dead, then locking in Eddie and Lily to die in the explosion as he, Paul, and their staff flee the site.

Paul is shown dictating a memo to Anita in a chauffeured limo, informing the Director of the CIA that "...C-System [is] no longer a viable entity."

The film holds an 18% rating on Rotten Tomatoes based on 33 reviews, with the site's critical consensus stating, "Ironic given the scientific breakthrough at the story's core, Chain Reaction is a man-on-the-run thriller that mostly sticks to [the] generic formula.

[8] Chain Reaction debuted in fourth place at the box office behind A Time to Kill, Independence Day and Matilda, collecting a total of $7.5 million during its opening weekend.

A character in the film claims that a glass of water could power Chicago for weeks, but no clear explanation is ever given as to whether this is by simply burning hydrogen released by highly efficient means or through nuclear processes.