The Minnesota author of “The Twenty-Ninth Day” (Blackstone Publishing) described his new book as a mix of “Wild,” “Between a Rock and a Hard Place” and “The Revenant.”

Overstatement maybe, but his tale of surviving a grizzly bear’s attack and the aftermath is, like the aforementioned titles, intense and compelling. (Related story here.)

In 2005, Alex Messenger, then 17, took a wilderness adventure with a guide and four other teenagers. Arranged by the YMCA’s Camp Menogyn, the group planned to paddle and portage 550 miles through the Canadian tundra for 48 days. Dubbed “Hommes” (French for “men”), the trip is the pinnacle of Menogyn’s progression of longer and more challenging wilderness camping and paddling adventures.

Before Messenger gets to his pivotal confrontation, he writes well of the group’s challenges pre-attack: high winds that slowed their progress; iced-over rivers that required the paddlers to skid their canoes over frozen surfaces; swarms of biting black flies; and their resourcefulness at catching trout to supplement a dwindling food supply. The story reflects similar memoirs in the long bookshelf of adventure trip journals.

The pace quickens in the final third of the book. On the 29th day of the trip, Messenger meandered away from the campsite on an island on Princess Mary Lake. Reaching the top of a small ridge, Messenger came face to face with a grizzly bear just 30 feet away. Dodging and twisting, Messenger managed to avoid the first swipes of massive bear’s claws. Charging again, the bear mauled Messenger, delivering deep bite wounds.

Unconscious after the attack, Messenger wakes, takes stock of his bleeding injuries and stumbles back to camp shouting, “Bear!” to an incredulous group of campers.

The group leapt into action, paddling 60 miles and enduring cold and long portages around white-water rapids, all the while carrying the emotional load of their constant concern for their injured friend.

Messenger describes the attack, the immediate aftermath and the six days that followed before a helicopter arrived to evacuate him. There’s an honesty, intimacy and urgency in Messenger’s writing that captures a roller coaster of emotions he and his group experienced.

“The Twenty-Ninth Day” is the kind of book that requires the reader to set some time aside. Intrigued to find out what happens next, phone calls will go to voice mail and work deadlines will get postponed. His story is a solid addition to the genre of wilderness survival tales.