Uncertainty Principle (Numbers)

Plot summary

FBI Special Agents Don Eppes, Terry Lake, and David Sinclair stake out two banks that may be the Charm School Boys' next targets, based on a prediction from Don's brother, Dr. Charlie Eppes, who used probability theory and statistical analysis. The Charm School Boys, a nonviolent pair of bank robbers, rob the bank under surveillance. Terry and David's team attempt an arrest but become caught in a shootout with the robbers and accomplices. Don joins the firefight, then follows the ringleader into a building, where the robber overpowers Don, shoots him with his own gun, and flees.

Charlie arrives and sees Don being treated for a minor gunshot wound to his arm. At the FBI office, the team determines Charlie's model is the only lead. Horrified by the crime scene, Charlie withdraws from the investigation because his model assumed the robbers were nonviolent.

Don sends Charlie home, but Charlie instead works on P vs. NP in the family garage, a problem he had worked on before his mother's death. Don confronts Charlie, who expresses fear that Don will be fatally shot. The team discovers evidence that one robber was military-trained and that the robbers killed a computer programmer and stole his identity. Another bank robbery occurs, during which the robbers fatally shoot a bank president, and surveillance footage shows Don's gun at the scene.

Production

The episode is based on a series of bank robberies in Maryland in 2004 that were solved with the help of an Arkansas mathematician. The FBI called in the mathematician to predict likely bank targets, and the robber was arrested while selecting his next target. Series creators Cheryl Heuton and Nicolas Falacci decided early on to explore the emotional effects of cases on characters. In writing this episode, they wanted to show Charlie's reaction to the violent nature of Don's work, having learned that most real-life mathematicians dislike violence.

They incorporated elements from their earlier feature writing, including an opening shootout. Heuton and Falacci changed the title from "Cause and Causality" to "Uncertainty Principle" after including the Heisenberg uncertainty principle in the script, using it more as a metaphor for Charlie's decision to leave the case. To include an unsolvable problem, they asked Dr. Gary Lorden of the California Institute of Technology, who suggested P vs. NP, which describes the length of time needed to solve a problem compared with the number of steps.

Reception

The Friday night premiere of "Uncertainty Principle" drew over 15.46 million viewers on January 28, 2005. Critics were split. Mathematician Raazesh Sainudiin criticized the focus on Charlie's emotional response, while statistician Richard Penny noted Charlie confused the observer effect with Heisenberg's principle. Conversely, Cynthia Boris of DVD Verdict praised it as "likely the best episode ever," and Todd Douglass, Jr. of DVD Talk called it "solid...to make the payoff worth it."