It's usually easy to figure out how a criminal enters a crime scene, but in this case, it was far from clear.

It looked like the killer vanished in thin air, and perhaps he had.

The killer vanished in thin air, and the killer vanished in thin air.

Getting into medical school, it's the hope and dream of thousands of students who apply each year, then pray they'll be accepted.

Michael Andrade was one of those hopefuls.

He really wanted to be a doctor. He really wanted to help people.

Just recently my mom told me she used to tell him, don't worry, my girl, all your hard work is going to pay off.

Because he worked really hard at school.

In 2005, Michael was a pre-med student at St. Mary's University in San Antonio, Texas.

He decided not to live in the dorms, so he rented an apartment a few miles from campus.

He actually chose that apartment because it seemed more family oriented than the other apartments.

He said that was the one he felt safer at.

One morning in February of that year, workmen smelled smoke coming from Michael's apartment.

They noticed that the windows were coated with soot, and when they went to the door, it was unlocked.

And as soon as they opened the front door, smoke came building right now.

They were forced out because of the smoke. And when they went back in, they found Mr. Andrade laying on the bed.

Michael Andrade had been strangled to death.

His body was somewhat burned, but very little compared to if the fire would have taken over.

He was found with one of his arms, his right arm, in fact, back behind him, about belt high.

The period that he had been at some point tied up with his hands behind him.

There were no signs of forced entry, but electronic equipment was missing.

There was an entertainment center that had speakers hanging off the front of it, which appeared to have been connected to something, and that item was missing.

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