Kings of Pain

The crew finds out that the swamp may be manmade.

Adam and Caveman Rob wrap up the season in Indonesia, with the two worst bites to date, from a Giant Asian Centipede and a 16-foot Reticulated Python. Vomiting, stitches and rivers of blood make them ask if they are able to continue their research.

The guys encounter two legendary creatures of the Amazon: the Bullet Ant and the Piranha. After hours of pain from the Bullet Ant, Caveman Rob dips his blood covered arm in a tank of Piranhas. What follows is a bloody and painful mess.

A wildlife biologist and professional animal handler get bitten and stung by some of the most dangerous animals and vicious stinging insects in the world in an attempt to create a complete and comprehensive pain index that will ultimately help save lives.

An underwater hunt for the possibly deadly scorpionfish in the Baja, ocean leads to a toxic sting that puts Adam in danger and matches the highest pain score to date, while the Toe biter results in the weirdest pain profile yet.

In Africa, Adam and Caveman Rob search for the Nile Monitor Lizard and the Velvet Ant but are attacked by an even deadlier animal and are lucky to escape with their lives.

In Africa, Adam and Caveman Rob search for the Nile Monitor Lizard and the Velvet Ant but are attacked by an even deadlier animal and are lucky to escape with their lives. The guys experience a brutal bite that makes them question their mission.

Adam and Caveman Rob head to South Africa to face the giant Bark Scorpion, the tiny Uroplectes Scorpion, and the highly venomous Lion Fish. Big pain comes in small packages, and the effects of marine animals' toxins are truly the next level of pain.

In a Bolivian jungle, Adam and Caveman Rob pursue the fabled Executioner Wasp, Warrior Wasp, and Goliath Bird-Eating Tarantula. One causes a medical emergency, and another delivers a nightmarish bite that leaves Adam's arm partially paralyzed.

It's America vs Australia in a battle royale of pain administered by sharks. After getting stung by both, Adam and Rob realize that when their countries win, they lose.

Rob and Adam test the Yellow Head Moray Eel for possible venom effects, but must resort to a risky, bloody bite. But venom is not the issue for their next animal: the Electric Eel. The results are positively shocking.

Rob and Adam test the pain dished out by a trio of unlikely creatures commonly kept in home aquariums–and they proceed to ruin the image of a popular cartoon movie character for millions of children.

Some of the most painful animals can be found in your very own backyard. Rob and Adam take on an Assassin Bug, a Jerusalem Cricket, and the Brown Widow Spider–producing a record-setting episode of pain.

Adam thinks he’s getting his revenge on Rob for selecting tarantulas earlier this season by programming Rob’s phobia: centipedes. But the joke is on Adam when an American centipede produces one of his most painful bites ever.

In a tribute to the godfather of the Pain Index, Dr. Justin Schmidt, Adam and Rob tangle with a new batch of extremely painful–and deadly–insects. And one colony of ants kicks the Schmidt out of them.

Adam and Caveman Rob get bitten by one lizard whose venom is in doubt–but not its ability to latch on and tear flesh–and another whose venom is notoriously painful. The shocking results set new records for the Pain Index.

Adam has a phobia of tarantulas, so naturally Caveman Rob picks two of the world’s nastiest ones for them to endure, including a tarantula with the well-deserved nickname: “Orange Bitey Thing”.

Adam and Caveman Rob take on America’s biggest and most deadly scorpions. But their surprising result is a hugely painful wake-up call–and a new Scorpion King is crowned.