To many, George R. Plagenz is Cleveland's "holy terror." To him, nothing, apparently, is sacred.

That is because Plagenz is a newspaper reviewer and critic who ignores the theater, the dance, the symphony, movies and restaurants. His critical eye is focused on church services.

He has established himself as the Rex Reed and Duncan Hines of worship. "Churches have been immune to critcism for so long, and I thought it was wrong," said Plagenz, religion editor of the Cleveland Press.

Each week the 54-year-old newspaperman visits, unannounced, a Cleveland-area church and publishes a review of the service in the Monday paper. Churches and synagogues are judged on their music, the sermon and the friendliness of the congregation. The highest rating is 12 stars.

Plagenz, who describes himself as an "evangelical agnostic," is a Unitarian minister, a graduate of the Harvard Divinity School and former asistant minister at Boston's historic King's Chapel. When he began running his weekly reviews of worship services a year ago, he was called "blasphemous." His reviews were branded by some as "sacrilegious." And his 87-year-old mother told him she did not want him to visit her chruch.

"In the beginning," Plagenz said, "people thought I was rating God."

Now, a year later, there is little controversy over what Plagenz freely admits was a "gimmick" to get people to read religlion news.

After the suburban Christ the King Lutheran Chruch recieved only a nine-star rating, the Rev. Ward Potts called Plagenz a "spriritual detective" who "sneaks into our midst unannounced, pulls out his double-barreled typewriter and lets us have it."

Indeed, Plagenz, a tall, enthusiastic newsman who usually ends his conversations with a blessing, is not timid or without humor in his reviews.

He began one by saying, "The shoe was on the other foot yesterday. Instead of the Jehovah's Witnesses putting their foot in my door, I put my foot in theirs." He gave their service a seven-star rating, the low end of Plagenz' "average" range.

Plagenz attends services unannounced, is generally unrecognized, and judges congregations on how warmly they greet a stranger. However, sometimes he is noticed. One minister, when he spotted Plagenz, told the congregation, "I guess this is the week we get our Nielsen."

A Jewish service reviewed a few weeks ago received an 11-star rating, and Plagenz said, "I couldn't have been wearing a yarmulke."

One of the three churches to receive a 12-star rating was St. Augustine's Catholic Church, where the newsman reviewed a mass for the deaf.

"There was no pomp or circumstance in the service. It was utter simplicity-but there was beauty just the same. It was the bauty that comes from true simplicity," Plagenz wrote.

One church that received a nine-star rating put a sign on its front lawn that read, "Approved by God & Plagenz."

If they are amusing, the reviews are not without conviction.

"Churches are having trouble growing, and one reason might be there is something wrong with their worship services," Plagenz said. "The worship service is the No. 1 evangelical arm of the church. If it fails, none of the other church avocations are going to draw people in."

Plagenz said that he asks himself, while reviewing a service, "How does it impress me? How does it impress others? What's not going on here that's keeping people away?"

An accomplished preacher himself, Plagenz says that many pastors and rabbis today do not "have any enthusiasm."

"I love to preach. I get up there and I say it and I feel it," he said.

Plagenz, who also writes syndicated columns for the Scripps-Howard chain of newspapers and United Features Syndicate, believes "there should be an adversary relationship between churches and newspapers.

His reviews, he says, "haven't had any real effect but they make good reading. Ministers are hard-headed. They don't want to change. I've given them good suggestions, but ministers take criticism badly."

Not all of them, apparently. The Rev. Potts concluded that "it was Jesus who moved upon the keys of Mr. Plagenz' typewriter. The Lord had a word to get to one of his parishes-not a glowing, glorious work filled with praise and compliments but a 'word of correction,' a word of rebuke. A tough pipp to swallow.