Maybe you’ve seen Bruce Lanterman sitting in a blue folding chair in Union Square Park handing out fliers with a photograph that now makes his heart ache.

For almost a year and a half, Mr. Lanterman has been handing out information in Union Square and on the streets of the East Village looking for leads into the disappearance of son, Douglas, a former resident of the neighborhood.

“I feel like I owe it to Doug,“ he said.  “I owe it to myself to give it the best shot I can this year to find him.”

Courtesy Lanterman Family Douglas Lanterman.

Doctors diagnosed Mr.’s Lanterman’s son with bipolar disorder in December 2007.  Over the next two years, he alternated living with his parents in Hackettstown, N. J., and with his brother in an apartment on East 11th Street that they had shared since 2003.

But investigators said that on March 13, 2009, the younger Mr. Lanterman boarded the wrong bus when he was returning to Hackettstown from his job in the Financial District and ended up in Pennsylvania. Mr. Lanterman said that the next day his son called and asked to be picked up.

But Mr. Lanterman said that when he and his wife, Carole, arrived to pick up their son, he refused to get into the car and they have not seen him since. “He just seemed like it wasn’t him, like he was being motivated by something else,” Mr. Lanterman said.

Since a reported sighting in Union Square Park last October, Mr. Lanterman is convinced his son is in New York City. So three days each week, Mr. Lanterman wakes up at 5:30 in the morning, climbs into his white GMC Envoy SUV, and makes the 40-minute drive from Parsippany, N.J., to the East Village.

He usually parks in front of his son’s old apartment, a red brick tenement building across from Webster Hall, because he does not have to get up from his post to feed the meter.

He sets up his chair in the shade under the subway awning in the park and tells visitors about the $2,000 reward for information about his son. All while a laminated sandwich board with the word “MISSING” scrawled above a grainy, blown-up picture of “Dougie” rests at Mr. Lanterman’s feet.

“I know it’s hard, but I’m hoping somebody will recognize him,” he said.