FBI agent Don Epps recruits his younger brother, a brilliant mathematician, to search for a serial rapist who is starting to murder his victims.
Don asks Charlie to try helping with the location of serial bank robbers. But despite his accuracy, an agent dies in the process because Charlie fails to take into consideration the robbers' motives.
When seemingly unrelated people in Los Angeles start coming down with a mysterious illness the FBI is called in to discover where the outbreak began.
An engineering appears to have killed himself, but Charlie isn't sure. So he has Don begin an investigation into the student's background and who may have wanted to murder him.
A mathematician's daughter is kidnapped just before he solves the Riemann hypothesis, a mathematical puzzle worth millions of dollars.
Don investigates railroad negligence on the part of the National Transportation Safety Board. When he starts to see a numerical pattern, he asks Charlie to help him figure out what the problem is and how to solve it.
When Don and his team start to investigate some teenagers they find themselves pulled into a counterfeiting case.
New information arrives on an old case, promting Don to think he sent the wrong man to prison.
Don and his team must stop a sniper who is randomly killing people.
Los Angeles is threatened when the hijackers of a truck carrying radioactive materials promise to detonate a dirty bomb.
Don and his team must investigate when a computer researcher working on a classified government project is found murdered and the data from his computer is stolen.
Don's investigation of a UFO that's been flying dangerously close to Los Angeles, turns into a murder investigation.
Don tracks down two dangerous convicts who escape confinement when their bus is involved in a traffic accident.