Uncertainty Principle is the second episode of the first season, and the second episode overall. It was released on January 28, 2005.
A pair of bank robbers are quietly taking LA by storm but Charlie delivers an equation that may predict their next location. Unfortunately, these bandits aren't as gentlemanly as the bank videos suggest.
Two men approach a bank teller and walk away with a paper bag. Charlie is watching the koi fish in the Eppes' backyard pond with Larry as he explains about his new equation to help the FBI predict new targets and times for a spree of bank robberies done by the 'Charm School Boys'. Don and his team are spread out between two different banks, while Larry cautions Charlie on his methods.
The Charm School Boys show up at one of the banks and the team readies itself. They confront the men and find out that there are more than just two men in the team when they open fire on the FBI. One agent is injured in the shoot out. Don arrives on the scene from the other bank to help his team. Larry and Charlie see the shoot out on the news. Don gets the injured agent out of harm's way, but he is already dead. David takes down one of the robbers. In the end three people died in total.
He follows a suspect (one of the original two men) who blows up a car. A getaway car drives away, but Don sees the man walking away. He and Terry run after the suspect. The man attacks Don and steals his gun. He runs when Terry shows up and fires at him. Don and Terry try to catch up with the man, but all they find is some random material.
Charlie arrives on scene to see the aftermath. He is shocked by what he sees. He finds out that Don is ok and promises that he won't tell Alan about what happened.
Back at the FBI bullpen the core team are talking about what happened. The office had only lost two agents in five years up until then. Don worries about how to tell the family of the dead agent what happened. He checks in with Charlie on his progress with the new data. He uses Heisenberg's Uncertainty Principle [see Trivia and Goofs below] to explain how things have changed. Charlie is sent home as Don presses him to figure out a new target or how to find the suspects while Terry says that if he needs to talk to somebody he just needs to call her.
The FBI team is trying to find the suspects. A tech tells him that the random material was a micro-mask. A thin mask that can obscure facial features, but not hinder the wearer.
Charlie goes into the cluttered garage at the Eppes' house and clears space to work and has told Amita that he won't be 'coming into work for a while'. Larry is clearly worried about his friend when he confronts him about this. Don shows up at the house and tells Alan what happened earlier that day. Don finds out that Charlie is working on P verses NP - an unsolvable maths problem - rather than an equation for the FBI case.
They ID a man named Malcolm Stapleton as a part of the robbery team. A neighbour says that she recognises the man in the ID photo as Bill Stapleton, Malcolm's brother, but he is an only child. They find Stapleton dead in the basement of the apartment building. The man who killed him was tortured and was killed in a way that is common to special forces.
The Charm School Boys hit another bank. The robbery happens as it had all the times before the one in the opening scene, however the bank manager follows them out and is killed with Don's gun.
Don tries to get Charlie to help, but Charlie isn't budging. That night Charlie and Alan talk about the end of Margaret Eppes' battle with cancer and how it effected the family.
The next morning Don and David talk to Stapleton's former boss. He informed his boss while on vacation that he had found a new job and wouldn't be coming back to work around the time he had been murdered. He had access to high level bank access at his job - something that could be useful to the robbers.
Captain Joe MacNevish from Delta Forces comes to talk to Don after the dead suspect was identified as Master Sgt. John Anthony Goldbrea. He points the team in the direction of Robert Gordon Skidmore, an associate of the dead man. This is the man who took Don's gun.
Charlie realises that the robbers had stayed on site at the banks longer than what they needed to do after they had the money they asked for. He uses Minesweeper as an analogy when talking to Larry about the problem.
He goes to the FBI to give the team his findings. He directs them to look for another man who was looking for data. They tortured Stapleton to get his credentials to get information about shipments of retired currency on its way to the Federal Reserve for destruction. The team gears up to take down the robbers.
A truck stops the SUV escorting the money and the team's comms go down. They stick to the agreed plan. They arrest one suspect and shoot another as Skidmore runs off. Don stops him as he tries to start his car.
Back at the Eppes' house Charlie and Alan are finishing dinner when Don walks into the house to join them. In a moment of growth, Charlie announces that he's giving up on P versus NP to pursue problems that he can actually solve.
- Rob Morrow as Don Eppes
- David Krumholtz as Charlie Eppes
- Judd Hirsch as Alan Eppes
- Alimi Ballard as David Sinclair
- Sabrina Lloyd as Terry Lake
- Peter MacNicol as Larry Fleinhardt
- Alan Davidson as Robert Skidmore
- David Carrera as Adler
- Robinne Lee as Agent Larkin
- Andrew Caple-Shaw as Agent McKnight
- Sam Wellington as Bank Manager
- Kenneth Meseroll as Captain Joe MacNevish (credited as Ken Meseroll)
- Susan Beaubian as FBI Tech Agent #1
- Matthew Yang King as FBI Tech Agent #2
- Ajay Mehta as 'Y' DS Manager
Don and Charlie graduated high school on the same day.
The explanation of the uncertainty principle in this episode has been confused with the so-called observer effect. Both are aspects of quantum mechanics, but the uncertainty principle states the impossibility to measure the value of some pairs of variables (so-called conjugate quantities) like location and speed of a particle at the same time with absolute certainty, while the observer effect states that observing an object always has an effect on the object.
Alan's wife, and Charlie and Don's mother, died of cancer.
When he was three, Charlie could multiply four digit numbers in his head.
The local news station shown in this episode was Channel 8.
Charlie talks about Heisenberg's Uncertainty Principle, from which the episode title is derived, but confuses it with the Observer Effect, which the episode really is about and should have been titled after. The uncertainty principle deals with measurement, and not observation.
Captain MacNevish wears "combat leader identification tabs" on the shoulder loops of his uniform. Delta Force staff officers would not wear these on their shoulder loops.
[This appears at the beginning of the episode] 16 Banks Robbed, 2 Suspects, $2,700 Average Take, 0 Weapons Used