David A. Curran was 21 when he was last seen in San Francisco on October 18, 2014. Originally from New York and having lived in Arizona, he disappeared without a trace and has not been heard from since.

He is described as 5 feet 10 inches, about 185 pounds, with brown hair and brown eyes. A distinctive tattoo on his left arm shows the molecular structure of an atom: five legs connected to a pentagon with a sixth line sticking out.

The San Francisco Police Department is leading the investigation and the case remains open and unsolved. If anyone knew David or has information about his whereabouts in San Francisco around October 18, 2014, please come forward.