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Dan O'Brien 1977
Dan in 1977
Dan O'Brien 2005
Dan in 2005
Dan O'Brien
Portrayed by Gary Hoffman (1977)
W. Morgan Sheppard (2005)
Episode Creatures of the Night
Status Alive

Dan O'Brien was manager at the apartment building where Mike Cahill worked as a doorman from 1975 to 1977. Dan thought highly of Mike and, years later, would say he was probably his favorite employee, often going the extra mile for tenants.

Dan noticed Mike was especially close to the older and married Helen Hargrove, who often stayed in because of her growing agoraphobia. Dan overheard Mike when he told Helen they needed to back off, or he would tell her husband Dennis Hargrove.

Dan, and the tenants were sorry to see Mike go when he quit soon after to pursue his dream of opening a coffee bar in New York. He never got the chance however, as he was murdered that very night.

Years later, in 2005, Dan was questioned by Detectives Nick Vera and Will Jeffries, asking if he knew of any link between Mike and serial killer Roy Anthony, who was suspected of killing Mike. Dan didn't know of any link between the two, but told them of Mike's relationship with Helen, and suggested that would have set off the now-deceased Dennis Hargrove if he'd ever found out about it.