A 4400 with the ability to induce rapid weight loss attracts the attention of Tom and Diana; Richard, Lily and their child find refuge in the company of a fellow 4400; a pop star endorses Jordan's cause; and Kyle is caught up in the frenzy when a frat party gets out of control.

The hunt is on for a shadowy killer after Maia has a vision of Jordan Collier's impending demise; Tom's personal life is disrupted by Kyle's frightening blackouts; Lily's reunion with her daughter Heidi irritates little Isabelle; Shawn offers sanctuary to a street urchin; and NTAC demands that Diana hand over Maia's diary.