When President Roosevelt's sons went hunting for the mystical panda

During the 1920s, dozens of expeditions scoured the Chinese and Tibetan wilderness in search of the panda bear, a beast that many believed did not exist.  When the two eldest sons of President Theodore Roosevelt sought the bear in 1928, they had little hope of success. But they ultimately introduced the panda to the West 

• Guest: Nathalia Holt, author of ‘The beast in the clouds: the Roosevelt brothers’ deadly quest to find the mythical giant panda’ (Simon & Schuster) 
• Producer: Ann Arnold