Sick Heart River is John Buchan's most powerful novel and his last, completed days before his death. It was published posthumously in 1941. Buchan's rich descriptions of the rugged Canadian Northwest Territories are influenced by his real-life voyage down the Mackenzie River in 1937. At that time, Buchan was Governor-General of Canada. The main character, the lawyer and politician Sir Edward Leithen—perhaps the most autobiographical of Buchan's characters—has been diagnosed with advanced tuberculosis and has been given a year to live. A former colleague, American John S. Blenkiron, requests help to find his niece's husband, who appears to have flown from his very successful financial career to the Canadian north. Leithen agrees to help.
The book was published in the United States under the title Mountain Meadow.