The trio who allegedly robbed and murdered 58-year-old Richel Nova were held without bail at their arraignment this morning on charges that they slaughtered him moments after he delivered a pizza to an abandoned home on Hyde Park Avenue, Suffolk County District Attorney Daniel F. Conley said.

ALEXANDER GALLETT (D.O.B. 4/28/92) of Hyde Park; his girlfriend, YAMILEY MATHURIN (D.O.B. 2/25/93) of Mattapan; and MICHEL ST. JEAN (D.O.B. 8/3/90) of Hyde Park were formally charged in West Roxbury District Court with murder for allegedly stabbing Nova to death on the night of Sept. 2. They are additionally charged with armed robbery for taking a quantity of cash from Nova during the attack and breaking and entering for unlawfully gaining access to the unoccupied residence where the incident unfolded.

“Every new piece of evidence we uncover makes this crime more despicable,” Conley said. “Taken together, they paint a picture of almost unbelievable malevolence.”

Assistant District Attorney Jennifer Hickman of Conley’s Homicide Unit told Judge Kathleen Coffey and a courtroom packed with Nova’s friends and family that Mathurin called for a pizza delivery to 742 Hyde Park Ave. using a neighbor’s phone and gave St. Jean’s cell phone as a call-back number. She allegedly inquired whether the deliveryman would be able to break a large bill, and was told that drivers carried only $20 in change.

When Nova arrived with the delivery, Hickman said, Mathurin lured him around back and inside by telling him that her wallet was inside. In fact, prosecutors allege, her two co-defendants were lying in wait with knives, prepared to kill him and take his money. They attacked almost as soon as he entered the residence.

Nova suffered multiple stab wounds to his chest, back, and throat that left him mortally wounded. Based on evidence at the scene and post-Miranda statements by all three defendants, investigators believe that they rifled through Nova’s pockets as he was dying.

Gallett, Mathurin, and St. Jean left the scene with Nova’s cash and the pizza. They drove away in his car, which showed signs of a cleaning attempt when investigators located it the next day. Under an adjacent vehicle, investigators found a pizza box that still contained three slices of pepperoni pizza.

Boston Police responded to the scene shortly before midnight after receiving calls from civilians who may have heard the fatal struggle. Nova was pronounced dead at 12:05. Investigators received significant community assistance during the days that followed, leading to the suspects’ arrests Friday night.

Catherine Rodriguez is the DA’s assigned victim-witness advocate. Gallett, Mathurin, and St. Jean are represented by attorneys Peter Krupp, Steven Sack, and Jeffrey Karp, respectively. They will return to court on Oct. 4.