H.I. No. 21: Cave Troll in Your Pocket

"Cave Troll in Your Pocket"
	Hello Internet episode
Episode no.	21
Presented by	CGP Grey; Brady Haran;
Original release date	September 20, 2014
Running time	2:09:56
Episode chronology
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	List of Hello Internet episodes

"H.I. #21: Cave Troll in Your Pocket" is the 21st episode of Hello Internet, released on September 20, 2014. It is the first episode of the podcast's third season.