The government lost a hydrogen bomb around Tybee Island, Georgia, in 1958, or is that an old wives' tale?

If it is only a tale, then why are three young men trying to find it, in hopes of selling it to make a dirty bomb?

Before the week is out, six friends from Kentucky will get caught up in kidnapping, murder, and treason, while trying to save one of their own and perhaps the citizens of Tybee Island and Savannah, Georgia.