It's been one year since the 4400 returned. After a period of intense medical observation, Tom has returned to NTAC in a limited capacity, assigned only to desk duty. Diana, having been through a series of inept partners, finally finds a way to cut... (more) through the red tape and get Tom back, all while in the midst of formally adopting Maia. Meanwhile, Richard, Lily and the baby are still living in meager conditions in a mountain cabin far away from Jordan. Jordan has now closed Arcadia Estates, and is on the verge of opening "The 4400 Centers," a place for non-members of the 4400 to discover "the 4400 within themselves." Collier becomes Shawn's guardian, and enlists him to heal important benefactors of the Centers.

Avery Tiplady, Bill Mondy, Charles Napier, Darryl Quon, Dawn Chubai, Grace Bauer, Graeme Duffy, Hiro Kanagawa, Jason Griffith, Julian Christopher, Michael Ryan, Nick Misura, Noah Beggs, Patricia Harras, Rob LaBelle, Sean Tyson, Summer Glau, Trevor Roberts