Don and his team are out to protect former radical Benjamin Polk from a determined sniper who wants him dead, and who is leading the FBI on a cat-and-mouse chase as he closes in on his prey.

When two FBI agents, part of a unit headed by Don’s former mentor, are killed during a shootout with bank robbers, the team must investigate what exactly happened. Also, Charlie and Amita worry when Larry opts not to attend a conference in Geneva.

To find the person behind a deadly gambling ring that is running a high-stakes Russian roulette tournament, Don and his team are called in to investigate. Elsewhere, Don and Charlie become concerned over the financial health of Alan.

The team investigates several deaths that turn out to be copies of a soon-to-be-released movie, while Larry goes on his own personal adventure.

The team attempts to find the daughter of a geneticist who they suspect was kidnapped by the unstable mother. However, they become concerned about the case when they find evidence that suggests the young girl was a clone. Meanwhile, Charlie and Amita discuss having kids and Liz reveals a dark secret.

The team investigates a decommissioned air base after a woman is found dead there, but their investigation is interrupted by paranormal happenings.

The team conducts an undercover sting to locate a cyber crime lord, but the operation is foiled by a charming, brilliant hacker whose desire to take over the online black markets puts him in a dangerous online turf war that could lead to murder, onNUMB3RS, Friday, Nov. 6 (10:00-11:00 PM, ET-PT) on the CBS Television Network.

Ian Edgerton meets back up with the team, but this time - he’s on the wrong side. Accused of murder, Ian takes a member of Don’s team hostage in order to get to the bottom of the case against him...

Don and the team needs help from convict John Buckley when robbers hit a diamond exchange and take hostages. They believe the robbers are copying Buckley’s criminal strategies.

When the FBI takes down a gang responsible for a series of armored car robberies, the aftermath reveals something quite interesting, which is that some of the bills in the car were flagged as part of the infamous and unsolved D.B. Cooper hijacking. The team calls in Agent Roger Bloom, who happened to have worked on the original investigation, for assistance.

The team investigates the theft of scratch-off lottery tickets, but the stakes are raised when they find out a culprit, who was killed at a botched robbery, turns out to be a former lottery winner. '

The team searches for a lost shipment of high-caliber firearms when one of the weapons is responsible for random killings throughout the city. Also, Charlie and Amita disagree on a wedding date while Don re-evaluates his relationship with Robin, on NUMB3RS, Friday, Jan. 15 (10:00-11:00 PM, ET/PT), on the CBS Television Network. Guest stars include James Remar as weapons dealer Randall Priest and Jon Seda as arms broker Lonnie Moses. John Cariani reprises his role as Professor Otto "Otto-Bahn" Bahnoff

The team hunts down a serial killer who is targeting men who use prostitutes. Meanwhile, Colby and Nikki are involved in a car accident during the investigation. '

The FBI investigates a number of jewelry thefts at awards shows, but are thwarted in their attempts by uncooperative witnesses, celebrity has-beens and fake gems.

The murder of two men takes the team to investigate a group of friends that had been sexually assaulted by a teacher at a younger age. Meanwhile, the perfect job opportunity pops up for Charlie and Amita, that may also put a wrinkle on their wedding plans.

After Charlie and Amita get married and begin preparations for their London adventure, they put a slight hold on their wedded bliss when they assist the team in helping Don track down the whereabouts of his gun after it goes missing.