police cars pull up. they get out, guns drawn. they order me out the vehicle first. they get me walking backwards to them with my hands up. >> reporter: and then, through all the terror and confusion, it dawned on kevin marsh. it wasn't him they'd come for. >> so then i see them getting robert out, kicking him by his feet, knocking him to the ground, ramming his face into the asphalt, putting him in the handcuffs. >> reporter: the story the fugetts told the police? they had accomplices when they murdered ann charles, and one was robert davis. coming up -- >> i was scared. i was shaking. >> now it would be robert davis's turn in the interrogation room. >> why don't you tell me, robert, what took place that night. >> when "dateline" continues.