Robert Breen, 68, was found dead in his Baltimore home on Summerfield Avenue on October 3, 2017. Emergency responders arrived after a report of an unresponsive person and discovered Breen had sustained a fatal gunshot wound to the face; he was pronounced dead at the scene.

Investigators identified 45-year-old Joseph Masilek of New Windsor as the suspect. Police said Breen and Masilek were known to one another and had been involved in a dispute before the shooting. Notes at the scene, later attributed to Masilek, expressed remorse for the incident. Authorities searched for Masilek, who was believed to have fled in a gray 2002 Mercury Cougar, and on October 5, 2017 his body was found in wooded terrain in Severn, Maryland from an apparent self-inflicted gunshot wound. With Masilek the sole suspect, the investigation was closed.

Did anyone in Baltimore or New Windsor know either man or notice the Mercury Cougar in the days around October 3–5, 2017?