One of the hundred books a year I read:

Two best friends, Wynn and Jack, decide to canoe the Maskwa River in northern Canada. Sharing a love of mountains, books, and fishing, they expect nothing but days of paddling at a leisurely pace and evenings of campfires and reading.

When a wildfire threatens, they move quickly down the fog-shrouded river. They hear, but can not see, a man and woman arguing on the banks, but opt to paddle past. Later in the day, they decide to return upriver and ensure the couple is aware of the approaching fire. Once back, though, they can’t find them.

The next day, they encounter a man paddling alone. Is he the man? If so, where is the woman?

Their quiet vacation becomes a desperate wilderness survival in much the same way as a quiet, meandering river ultimately encounters white water.