"Aw, you're humming my balls!" -McCay's last words.
McCay (also "McKay") was a member of D.C.'s squad that was paid by Hunt to help him on his journey through No Man's Land to find "minerals."
While drinking in a bar, a man named D.C. is approached by a mysterious businessman named Hunt. Hunt offers D.C. six-thousand dollars for him - and a team of mercenaries - to lead him through an area that is known for its neutrality. D.C. accepts the offer, though he knows it dangerous. In thirty-six hours, D.C. has a team of five other mercenaries. D.C., McCay, Prior, Jordan, Taktarov, Cotter, and Voyteche were the members (along with Hunt).
Upon reaching their destination, and exploring The Bunker, Cotter and McCay find a breather within a pile of bodies. They nickname the breather, ironically, "The Breather." The Breather could not respond, walk, or use any motor skills. McCay, Voyteche, and Jordan all try to interrogate The Breather, to no avail.
Later, McCay sits The Breather down and attempts to interrogate him himself. As McCay leans down to sift through a box of files and board games, he looks up and sees that there are two figures standing on either side of The Breather. McCay freezes blink his eyes, then grabs his AK-47 and aims it at The Breather. D.C. then walks in, looks, and says "Checkmate?". McCay replies, saying "Just slipped on some lose gold, eh."
After Prior attempts to get The Breather to talk, McCay is next seen in the radio room. McCay was attempting to activate the radio. While attempting to turn it on, he accidentally activates an overhead system, which played German Polka music. The scene then cuts to D.C., who exclaims "Mac! Turn that shit off!". The scene then reverts back to McCay, who starts trying to turn it off. He unplugs many switches. He eventually shuts it off, right when D.C. walks into the room. McCay justs shrug his shoulders, and D.C. exits the room.
Other supernatural things occur to the team, including the death of Taktarov, Voyteche, and Cotter. Hunt shows the rest of the team what he showed D.C.; a film that showed the killing and testing of men for Nazi experiment purposes. While conversating of about the Nazis, Jordan notices The Breather on the screen and says "Guys. Hey guys! GUYS!". They all look, and Prior just had walked into the room. Prior whispers "Mother Fucka," and speedwalks to the room where The Breather is at. Prior pulls out his M9 pistol and shoots The Breather in the head. He turns around and says "Well that worked." Jordan asks "So we can kill them, right?". Prior replies "Well, his brains are all over the wall, that's good enough for me." The Breather then opens his eyes, sits up, cracks his neck, and begins to get up. McCay sarcastically yells "Aw, you're humming my balls!". Then the lights go out, then come back on. McCay was nowhere to be seen. D.C., Hunt, Prior, and Jordan here McCay screaming. They all race up to surface and see McCay, dead, tangled in the white flag Prior had hung up only moments before.
- McCay was played by the actor Michael Smiley.
- McCay was an Irish Republican and Paratrooper.
- McCay uses the Norinco Type 56 as his primary weapon.
- McCay's name is also spelt "McKay."
- McCay wears a red beret.
- McCay was the radio man for the squad.
- McCay was shot in the shoulder during the skirmish with "the shooter."