Up next, three women are in Florida on their first real vacation.

These women who were here by themselves thought, this is great.

We're seeing Tampa Bay.

The evidence suggests they took a boat ride and then disappeared.

But there was little else to go on.

There are hundreds, if not thousands of miles, to look over to find a piece of evidence.

Hair, fibers, any fingerprints would have been washed away.

But a public billboard turns citizens into investigators.

I thought it was an excellent idea, brilliant.

On a warm June morning in Tampa, Florida, authorities discovered the bodies of three women floating in Tampa Bay.

They knew that there was foul play because the women were tied up and had bricks around them.

The victims had their mouths taped shut, were naked from the waist down, and had been bound with yellow rope. It was horrible. It was terrible. It was beyond comprehension to think anyone could do what was done to those girls.

The first question facing investigators was the identity of these three women.

There was no ID, so we weren't able to identify who these individuals were, where they came from,

and who they might have had contact with prior to this event.

Although each victim was tied to a 30-pound concrete block,

decomposition created gases that lifted both the bodies and concrete blocks to the surface.

The water temperature was hot.

Had this occurred in much colder temperatures, much colder water, one center block might have held them under the surface.

You'd have to do a lot of study on that to figure that out.

The medical examiner estimated the bodies had been in the water for at least three days.

To pinpoint where the victims were put in the water, investigators asked the University of South Florida to analyze the currents for that time period.

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