The Dartmouth Murders

Officers secured the area and called more officers, together with forensic criminologists, to the scene.

There was no sign of forced entry. 

The wooden floor had a partial bloody boot print on it.

Two items found amid the shambles looked distinctly out of place: 12-inch-long black plastic knife sheaths, each embossed with the letters SOG. The weapons were nowhere to be found. However, investigators surmised that two sheaths meant that there had probably been two weapons and two killers.

Had the killings been planned? That sort of murder would usually be committed with a gun.  These were messy killings. Writing for The New York Times, Carey Goldberg quoted Audrey McCollum as saying her physician husband said he found the scene "the most awful thing I had ever seen."

If the killings had been planned, why had the killer or killers been so careless as to leave the sheaths of the knives behind?  On the other hand, if the killings had happened spontaneously, as the culmination of an argument, why would a pair of combat knives have been brought to the house?

Book Cover: The Dartmouth Murders

Experts believed it unlikely theft could be the motive because so much of value had been left. As Eric Francis wrote in The Dartmouth Murders, "Less sophisticated burglars could be expected to miss the significance of the Rodin or the valuable paintings and antique books, but the killers had also bypassed the abundant silver in the front room, dining room, and kitchen, and the diamond-encrusted pins, earrings, and other jewelry that Susanne kept in her bedroom. Not to mention the expensive Apple computers, stereo equipment, televisions, and appliances all around the house."

Half's wallet was missing but authorities thought it unlikely someone who had come to steal would not have taken more.

The lack of evidence of forced entry suggested that the killers were people whom the Zantops knew. The means of murder pointed to a close relationship between killers and victims. Stabbing involves a terrible intimacy. The killer is splashed with the victim's blood and is close enough to hear the screams and feel the struggle of the dying. Attackers who stab are usually enraged, and that rage is typically directed specifically at the people they are stabbing.

Determined to discover who harbored such fury at Half and Susanne, the investigators closely examined their backgrounds.