River Monsters (2009)

S04E05 Russian Killer

Title: Russian Killer Plot: The unsettling vanishing of three men in eastern Russia presents a perplexing challenge for Jeremy Wade. During his inaugural trip to the country, he embarks on a three-day exploration of the Amur River, determined to unravel the mystery behind the fishermen and others who have tragically perished in these waters. The leading suspect is a massive predator weighing over a ton and measuring more than 18 feet long; however, Wade faces resistance at every corner as locals refuse to assist him in the hunt. This pushback leads him to suspect that a sinister truth lies hidden beneath the surface.