Private Nick Gillis was a character who appeared in the Season 10 episode of the CBS-TV series M*A*S*H titled "A Holy Mess". The part of Pvt. Gillis was played by actor Cyril O'Reilly.
About Pvt. Gillis[]
When Gillis wanders into the Mess Tent and sits down next to Hawkeye and B.J., he seems nervous and sullen, so they ask him if he wants to talk. He's reticent at first, but when they invite him back to the Swamp for drinks he accepts. Gillis opens up to Hawkeye and B.J. He admits that he's AWOL, and then tells them why: he just found out from a friend that his wife has had a baby - even though he's been in Korea over a year.
When Gillis, upon the surgeons' suggestion talks to Father Mulcahy after the camp Sunday services, Lieutenant Spears (David Graf),sent by Gillis' commander, steps in and demands that he comes with him. Gillis refuses, and, grasping, claims he has a right to Sanctuary, since he is, in effect, inside a church. Father Mulcahy agrees with Gillis' point of view, and grants him Sanctuary. Col. Potter is dubious, but goes along with Mulcahy until he can get further instructions from command.
He and Spears calls the Judge Advocate General. In the meantime, Mulcahy and Gillis get to know each other. He tries to show sympathy for Gillis, but warns him that, after thirty days, AWOL becomes Desertion, a much more serious military offence. Eventually, the JAG rules against Mulcahy. But Mulcahy still won't relent, saying he will only follow the advice of Command Chaplain at I-Corps. Spears can't believe what he's hearing, and insults Mulcahy, which Potter angrily slaps down. Word from the Command Chaplain arrives, and Potter agrees with the Army - the Mess Tent is not a church, therefore no Sanctuary. But Mulcahy still disagrees.
Fed up with Gillis' stance, sends in some MPs to get him, Gillis panics, and grabs his rifle, preparing to fire. Mulcahy gutsily grabs it, knocking the barrel into the air. The gun goes off, causing everyone to hit the dirt, and Gillis ends up pointing it at Mulcahy, who angrily stares Gillis down, rebuking him for "taking refuge in this house of the Lord when it serves your purpose", and then his willingness to "desecrate it by pointing a deadly weapon at another human being!" Reminding him that "A faith of convenience is a hollow faith", Mulcahy is able to grab the rifle out of Gillis' hands and throw it away, and Gillis apologetically collapses into tears in Mulcahy's arms.
Later, we learn that it turns out that JAG is merciful enough to arrange for Gillis to be treated by Dr. Sidney Freedman, and he's "being treated like a casualty, not a criminal."