The phrase "masked killer" refers to a person who hides their face using a mask and commits acts of violence, usually in movies or stories. Full definition
The soft voice masks a killer, but why? (tollbooth.org)
Add into the mix a subplot involving Hans» cancer striken wife and a mysterious masked killer who is going around taking down underworld figures, and «Seven Psychopaths» has a lot of narrative balls to juggle, and doesn't always handle them satisfactorily. (indiewire.com)
Halloween (AMC, 8:30 p.m.): Have you seen John Carpenter's 1978 film about masked killer Michael Myers, and resourceful babysitter Laurie Strode (Jamie Lee Curtis)? (avclub.com)