"All the Way Home" requires a keen sense of balance. A production of it should exercise the mind as well as the tear ducts.

The Olney Theatre production succeeds on both counts.

Jay Follet, the most significant character in Act 1 of this Tad Mosel dramatization of James Rufus Agee's "A Death in the Family," disappears after that act, returning only for the curtain call. In the second act we learn he has been killed. In the final act his family returns from the funeral and adjusts to life without him.

The play shifts its focus from nostalgic heartwarming (Act 1) to a tale of personal heartbreak (Act 2) to a meditation on the social rituals and attitudes surrounding death (Act 3). The title, "All the way Home," leaves behind its original connotation of a return to the security of the hearth and embraces the total insecurity of death instead.

The cast must be able to make this journey along with the play, and Olney's players come through admirably.

Pat Karpen delivers the key performance as Mary Follet, wife of Jay and mother of 6-year-old Rufus. Mary's devout Catholicism is suddenly tested in May 1915 when her husband is killed. Her "pursed lips" faith does not survive intact, but Mary herself does, and Karpen is at the top of her considerable form as she enacts the metamorphosis.

The Agee figure in the play, little Rufus, is portrayed by Guy Michaels, 10, making his professional theater debut. The performance is most adept in its lighter moments; the dark spots are less convincing. It's a formidable role for a performer of any age, for the actor must comprehend that the character's sorrow is largely uncomprehending.

As Jay Follet, David Snell completely sheds the sinister trappings he adopted in Olney's "The Caretaker" and becomes a paragon of fatherly warmth while still maintaining an edge of restlessness. This is a triumphant summer so far for Snell.

Director Leo Brady has found an accurate and sympathetic gallery of supporting players. They move through Joseph St. Germain's evocatively lit set with ease.

Fans of "Well-made plays" may be bothered by the changing focus of "All the Way Home." At first the play seems to belong to Rufus and Jay, then to Mary, then to Mary and Rufus.

Agee's book was unfinished when he died in 1955 on the anniversary of his father's death. However, considering that the novel was assembled and the play adapted from autobiographical fragments, the result is remarkably coherent even to people who have never heard of Agee.

At least at Olney, the shifting focus makes no difference. The point of view in "All the Way Home" is Agee's, not his characters", and he perceives images that all of us can understand.