Mark David Zeichner, 34, was last seen on June 15, 1984, in Teaneck, New Jersey. He lived in an apartment in Queens, New York, but vanished without taking any of his personal items; his clothing, wallet, identification and toothbrush were all left behind, suggesting an abrupt departure. No confirmed sightings or significant leads have been reported since.

Mark had been diagnosed with bipolar disorder and schizophrenia, had a history of resisting prescribed medication, struggled with drug use and had previously attempted suicide. He was white, about six feet tall and 180 pounds, with brown hair and brown eyes, may have worn a mustache and had scars on both wrists. He was last seen wearing a circular metal band on his wrist. His mother believed he might be living homeless, a theory that has not been substantiated.

Does anyone in Teaneck or Queens remember Mark or have information about his whereabouts after June 15, 1984?