Discovering that NTAC is behind the disease plaguing the 4400s, Tom and Diana try to get to the bottom of NTAC’s cover-up, while Kyle considers turning himself in.

A morbid premonition from Maia threatens the future of the 4400 Center.

Tom and Diana investigate a 4400 junior high school teacher accused of child abuse.

Tom and Diana investigate a 4400 whose ability to increase the human bodies’ metabolism just may be this weight-conscious world’s answer to the ultimate fat-burner.

A returnee exhibiting telepathic abilities seeks help from NTAC, but is instead used as a mole to infiltrate Jordan Collier’s 4400 Center.

Richard must protect his family when he and Lily are discovered to be 4400s.

Tom and Diana investigate a mysterious structure being built at a psychiatric hospital, based on the drawings of one of their patients who’s a 4400.

Diana helps Tom break Kyle out of NTAC quarantine, eventually leading them to discover the truth behind the 4400.

Tom and Diana investigate Oliver Knox, a 4400 suspected of being a serial murderer.

Tom and Diana continue their investigation on Jordan Collier’s plan for mankind. Dennis Ryland rejoins NTAC. Isabelle prepares for battle.

NTAC and the 4400 Center work together to find Jordan Collier. Kyle Baldwin gets a surprising visitor at the state prison.

Allison’s baby shower fetches her a load of eco-friendly gifts and the discovery of a drowned scientist in a location where drowning is impossible.

The whole radio station is buzzing over the incredibly attractive and talented new radio host, Dr. Clint Webber. Frasier tries desperately to find Clint’s “Achilles heel,” while Martin is thrown…

Stardate: 42402.7 The Enterprise is placed in a compromising situation when the captain of a disabled starship places the crew in the middle of a love triangle.