* Fiction. By Frank Delaney. Random House, $26 . Grade: B+

Plot in a nutshell: Robert Shannon, a young American priest, returns to Boston from France at the end of World War I. He has been a chaplain and, having seen far too much of battle, is now shellshocked. He is badly in need of recuperation, but back at home he inadvertently witnesses some deep-seated corruption at the highest levels of the church hierarchy. A friend and mentor sends him to Ireland, the land of his ancestors, to find some peace and regain his health; this trip also suits the needs of his superiors who want to be rid of him.

There isn't a lot of peace in Ireland at this time, and Robert has more than one ugly encounter with armed men. But as he travels through Ireland, following his namesake river, the Shannon, he is met with friendship and kindness as well; his mentor has told people his story and prearranged for them to take him into their homes along the way.

Every encounter he has, whether for good or evil, serves as a lesson and guide on his way to recovery.

Sample of prose: "With the house of the yellow door behind him and his visit there undetected, Robert breathed again. By now, the shy advance of dawn had fully spread its light. The path rambled between the river and a small country road, toward which Robert cast an eye every hundred yards or so. He walked on, wary but not anxious. All around him the vegetation provided deep cover, should he need to avoid a repeat of last night's fright."

Pros: Delaney, a native of Ireland and the author of several other novels, knows the territory. Ireland is a living place and its people compelling.

Cons: Shannon is a little overly long and slow-paced. It requires some patience.

Final word: Delaney is a skilled writer, and Robert Shannon is a sympathetic and credible protagonist.