Jericho

This is a great show on CBS. Here is the synopsis.

After mushroom clouds appear on the horizon, 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.

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