Mr. O'Malley  is a construction foreman who called the Extreme Ghostbusters for help.
On the weekend before St. Patrick's Day 1997, O'Malley was assigned to oversee a restoration job at the Sons of Erin Society Building. He ordered Mr. Murphy to clean out the office. He heard a commotion and rushed over. O'Malley saw the Leprechaun but blinked and it was gone. O'Malley called the Extreme Ghostbusters and showed them to the secret room Murphy found.