King Corn” is the 2007 film by best friends Ian Cheney and Curt Ellis, who document their move to Iowa to grow an acre of corn and study everything about the crop. The film shows how something as simple as corn can play such a big role in everything from skewed farm subsidies to diabetes to pesticide pollution. If you loved that film, you’ll be glad to know that the boys also made a thought-provoking companion film, “Big River.”

How is corn related to rivers? Well, most U.S. cornfields are treated with pesticides — and the impact of those pesticides can be felt downstream. In “Big River,” Cheney and Ellis take another trip — this time by canoe — from their farm to the Gulf of Mexico to see what effect their little farm is having on the rest of the world.

That 30-minute documentary is available on DVD, but will also air on Planet Green at 10 p.m. on Nov. 6. And in case you haven’t seen “King Corn” yet, you can just keep watching Planet Green — the original film air at 10:30 p.m. Or if you have a Netflix account, you can stream “King Corn” at your leisure, before or after watching “Big River.”

What 'King Corn' does to the 'Big River'
'Big River,' a companion film to 'King Corn,' explores the wide-reaching water pollution problems created by monoculture farming.