Overview: Professor Leif GW Persson investigates the unsolved homicide of Dennis D'Agostino in Nacka, 2000. Camilla Kvartoft visits Swedish Forencics Laboratory (SKL) in Linköping where she uses hand-guns and gets to know the basics of ballistics. A retrospective look at the terrorist attack against the West-German embassy in Stockholm, 1975, is also part of this episode.