When Sandra Allen was studying nonfiction writing at the University of Iowa, her Uncle Bob sent her the typescript of his autobiography. This would be her "crazy" Uncle Bob, a chain-smoking, good-natured, long-haired oddball who lived a hermit existence in California. The autobiography was typed all in caps, its curled pages stinking of cigarette smoke.

The spelling was haphazard and the prose almost unreadable, with no paragraph breaks. "Each page was a wall of text," Allen writes in "A Kind of Mirraculas Paradise," her memoir of her uncle's life.

She did not know if the manuscript was truthful, delusional or a pack of lies; it was pockmarked with racist and homophobic comments and disturbing confessions, and she had no idea what to do with it. So she stuffed it in a drawer and ignored her uncle's phone calls.

Eventually, though, she began to read, using it as raw material for essays and then this book. But she does not, or cannot, articulate why.

"Why did I choose to write about Bob? What interested me so much about his story?" she writes. "I've never had good answers to these questions."

This is ultimately the book's weakness — although Allen translates Bob's prose, researches his life and includes a lot of information about mental illness, the book lacks a strong central point.

And yet in its own way it is enthralling, offering a view from the inside of life with mental illness.

As a teenager, Bob was diagnosed as paranoid schizophrenic. He was in and out of psychiatric hospitals for many years, going off his meds frequently, cheerfully and for all kinds of reasons. (He forgot to take them. Or God said he no longer needed them.)

The book toggles between Bob's memoir and Allen's research. She does not reproduce her uncle's prose verbatim, which apparently would be unreadable. Instead, she translates it into proper English, preserving occasional all caps and some of the odd spellings and punctuations, perhaps to give a flavor of the original. But we lose something in not seeing those tobacco-browned pages as they are; we get, instead, a rewritten diary that sounds, well, perfectly sane.

Prettied up or not, Bob's writings are by far the most interesting part of the book. He presents his delusions as fact (being abducted and returned by aliens; predicting the 9/11 attacks decades before they happened; jamming with Kenny Rogers in the psych ward), and while Allen attempts to fact-check ("I tried to reach and never heard back from … Kenny Rogers") sometimes we never know what was real and what was not.

Although he does odd things — walks naked down the hallway of the hospital, waves a butcher knife around in a crowd — Bob never seems scary or dangerous, and perhaps this book will help readers understand that mental illness does not automatically turn people into murderers. Bob is endearing, fascinating and, almost certainly, exhausting — for himself and his family.

There are many places where Allen confesses that she is unsure of her material, or delivers information with little or no interpretation. She interviews Bob's parents and stepparents, and even when they disagree she draws no conclusions, just relates their differing perspectives flatly. At the end of the book she seems as conflicted about Bob's memoir as she was at the beginning.

And so we are left with Bob's words (Bob's heavily edited words). And maybe that is enough. Being inside his head, seeing how life felt and looked to him, is a miraculous thing indeed.

Laurie Hertzel is the senior editor for books at the Star Tribune. @StribBooks

A Kind of Mirraculas Paradise
By: Sandra Allen.
Publisher: Scribner, 275 pages, $26.