Mackenzie Hannigan

J.D. clears his schedule to help Dr. Cox but is pushed aside for a new intern; Turk nervously sends out the wedding invitations; Drs. Cox and Kelso fight for the attention of a female colleague (Bellamy Young).

Fear of the unknown propels Jericho into social, psychological and physical mayhem when all communication and power is shut down. The town starts to come apart at the seams as terror, anger and confusion bring out the very worst in some residents. Jake Green, the prodigal son of the town's mayor, becomes a reluctant hero when a school bus crashes as a result of the explosion.

Melinda's mysterious new neighbor is haunted by an old classmate's dead grandfather, who suspects Tom kidnapped and killed his granddaughter.

Jake organizes a group to gather more information about the explosions after a satellite television in the local bar broadcasts an Asian news program showing the extent of the nuclear attacks. In addition to the television broadcast, Stanley, who is hospitalized for radiation poisoning, claims to have seen tanks headed toward Denver. With Jericho still cut off from communication and the people craving information, Jake recommends sending out four search parties in different directions to get a sense of what is going on outside of town. Meanwhile, when one of the inhabitants dies unexpectedly, Heather questions the cause of his death.

The people of Jericho receive a pre-recorded phone call from Homeland Security telling them that help is on the way. The townspeople start to think that life might be returning to normal when the power and phones return. Their hope is dashed, however, after the power surges and electrical lines go down, causing fires to break out all over town. While, when Jake and Hawkins work together to fight the fires, they discover that neither one of them is who they claim to be. Meanwhile, still desperate for information, the townspeople vigilantly watch the satellite television in Mary's bar with the hope that another signal will come through.