The Equalizer (1985)

Robert McCall is a retired secret agent. Having become disillusioned by all the rigamarole that comes with secret agenting, McCall starts to look out for the little guy. Calling himself "The Equalizer," McCall puts ads in the paper marketing to desperate people in desperate situations. McCall usually takes these despairing cases for little or no money (he lives in a posh Manhattan apartment). Acting as both bodyguard and investigator, sometimes using his government resources, McCall usually manages to save the day.