This TV movie reunited Mike Connors and Robert Reed. Both appeared on Mannix (1967). Connors, of course played Joe Mannix, while Reed played recurring character Adam Tobias, a police contact and friend of Mannix.
The river in the movie is the Coquitlam River in Coquitlam, BC, Canada, which is a suburb of Vancouver but rural at the time of filming. The cabin and the interior, although different properties, were both on the same street near the river.