It's a complex story with many facets, but it that can be summarized like this: At 2 p.m., Harold Dahl was on a fishing boat salvaging logs with his young son when he said he saw six flying discs appear above him over the water.
One of the donut-shaped discs appeared to be in trouble and dropped what appeared to be tons of a hot molten substance in the water and the beach. As the story goes, the heat and debris killed his dog and burned his son.
Days later he was visited by a mysterious "man in black," who told him not to talk about what he saw. He was then visited by two Air Force investigators who were on a classified mission to see him and gather evidence. On the investigators' return to a California airbase, the B-25 they were piloting crashed, killing both of them and destroying whatever evidence they were carrying. The FBI closed the case without any resolution.
It's known as the Maury Island Incident.