The original Pilot of NUMB3RS was produced in 2004. Test audiences questioned the believabilty of the Eppes family being related. Cast and script changes led to the series being picked up by CBS. The series later premiered in 2005.

FBI Agent Don Eppes recruits his younger brother, a brilliant mathematician, to help search for a serial rapist who has begun murdering his victims.

Don recruits Charlie to figure out where bank robbers will strike next.

A deadly virus is spreading through LA and only Charlie's equations can determine how far and where the disease is spreading.

The mysterious suicide of a brilliant but unfocused CalSci engineering major leads Eppes and Charlie to the site of an iconic building.

A genius' (Harris) daughter is captured by two men looking to use his possible solution to a 150 year old math equation for heists.

An unknown terrorist is mimicking horrible train accidents and leaving a number code at the scene.

The investigation of two teens leads Don and his team to counterfeiting ring.

When Riley, who practiced an ingenious pyramid method of skimming numerous bank accounts for over half a million dollars, is strangled, exactly the same way -not revealed to the press- as Lisa Bayle, for whose murder Don Eppes' investigation once put Cliff Howard in jail after a plea bargain-confession, Don now fears the wrong man was arrested. Charlie helps him quantify the unlikeliness of a coincidence and seriously doubt the forensic evidence. Electrician Jose Salazar, whom Don suspects, still turns out to be innocent of Lisa's murder, but Charlie realizes that's not the point: what if a third person committed both murders, linked rather by the victims?

Don and his team call on a senior sniper instructor from Quantico to help stop a marksman who goes on a killing spree in Los Angeles.

A truck of nuclear materials is stolen by terrorists who intend to use the materials to make a bomb which would then be used on the city of LA. Only Charlie and Charlie's father Alan can save the city from a small nuclear blast.

Dr. Larry Fleinhardt's former college days friend Jonas Hoke, the Senior computer-science researcher, who develops for Robert Oliver's firm Lorman group with gifted college drop-out Scott Reynolds a classified program to evaluate government projects, is murdered in his Hollywood Hills home; data were stolen from his computer, which only contains a coded program for analysis of baseball statistics. Hoke's financial divorce complications seem irrelevant, although his wife had a relationship with their security system installer Lucas Grant. However Charlie finds that Hoke actually used the same kind of advanced statistic analysis and performance prediction on other data, cleverly masked under meaningless baseball numbers: Hoke applied this method cutting-edge to calculate human performance prospects in real life, based on various governmental and other data, potentially far more valuable...

Don asks Charlie to help determine a mysterious aircraft's point of origin and is surprised when the probe turns into a murder investigation.

Don and his team track two violent prison bus escapees.