Mike heads to Pennsylvania and tries his hand at making bologna and then goes to Alaska to repair a very special toilet.

Mike travels to Ohio to check on the Common Tern population and then he finds himself in Northern California plugging an abandoned mineshaft.

Mike takes a trip to the La Brea Tar Pits in Los Angeles to find out about the important work being done in Pit 91. Then Mike travels north where he learns about rendering and discovers how much of a farm animal can be recycled.

Mike heads to Meridian, California to find out what it takes to harvest walnuts. Then he spends some time in Tulelake where he learns how to make goose down pillows and comforters.

Mike journeys to Queen Creek, Arizona to press olives into oil and then heads to Sacramento, California to clean dirty diapers.

Mike ventures to Payette, Idaho to learn how to make high quality bird food. Then he heads to Yarnell, Arizona to collect spiders from the desert to milk them for their venom.

Mike heads to MotivePower in Boise, Idaho to build and restore locomotives for his 200th dirty job.

Mike takes a look back at his previous jobs, toughest co-workers, and his ongoing encounters with dirt and poo. With additional footage from "Skull Cleaner" and "Turkey Inseminator"

Mike takes the day off to get a physical examination, leaving Executive Producers Eddie Barbini and Craig Piligian to host the show: servicing porta-potties and making custom-fabricated alloy wheels for Boyd Coddington Wheels

Breeding and training Alaskan Huskies as sled dogs with Martin Buser; revisit of dirty jobs in Alaska: Bird ringing common terns and Canadian geese ("Abandoned Mine Plugger"), fishing and processing of fish ("Floating Fish Factory"), cleaning up diesel spill in Dutch Harbor, Alaska ("Ice Salvage Crew"), incinerating toilet cleaner ("Bologna Maker"). The mail bag portion was taped at the Soo Locks on the floor of the MacArthur Lock in front of the upstream bulkheads.

Mike finds out what happens to old mattresses after people throw them out.

High-rise window washer, viewer mail: brine tank cleaner (Shark Reef at Mandalay Bay)

Toilet Crusher & alligator snapping turtle researcher

Mike works at the country's only Dromedary camel dairy.

Mike recycles computers before heading to Hawaii to make tofu.

Mike goes to Jonesboro, Arkansas to perform dung beetle research. Then he heads to Williamstown, West Virginia to try his hand at making glass art.

Mike reflects back on his more hazardous apprenticeships and makes a case for safety.

Mike goes to Kentucky to try his hand at shrink-wrapping a houseboat. Then he heads off to Palmer, Alaska to spend a day working at a reindeer farm.

Mike goes to Hawaii to learn how to make dirt shirts at The Original Dirt Shirt Company. Then he heads off to Reno, Ohio to learn how to make marbles.

Mike becomes a specialty fireworks technician in Addison, Pa. and then helps examine a cow with a hole in its stomach at Arkansas State University.

Mike goes to Florida to harvest clams at the Alligator Harbor Aquatic Preserve and later attempt to worm-grunt in the Apalachicola National Forest.

Mike travels to San Francisco to participate in the messy process of paint bulking. Then he heads to Wagner's Sugar Camp in Pennsylvania to spend the day making delicious maple syrup the old-fashioned way.