As the first unhappy tornadoes of the season rip across the Midwest, the teams pick up the chase in Oklahoma. Veteran Tim Samaras finds a swarm of tornadoes that offer plenty of opportunities for deploying his science probes. Meanwhile, Sean Casey's new TIV Doghouse crew struggles to get him that inside-a-twister IMAX shot and the chase ends in a screaming match. But when Reed Timmer debuts his Dominator, he scores an unprecedented intercept.

Sean's frustrations with Reed boil over as they cross paths during a chase on the back roads of New Mexico. The next day everyone heads to the Texas Panhandle, but unhappy storms soon turn the dirt roads into quagmires that could trap the chasers at the worst of times. By the end of the day, Reed and Tim are trapped in the mud between two tornadoes but they seize the chance to get up close and film the unhappy twisters and deploy science probes.

Reed steps up his science to take on Dr. Josh Wurman's massive research project. Joel has second thoughts. The fallout reaches Sean, who makes a drastic decision.

As tornado potential skyrockets across the Missouri plains, Sean's prized TIV2 breaks down mid-chase and is left on the sidelines. Meanwhile, Reed's new data-gathering radar allows him to step up from aggressive chaser to extreme scientist, but his long-time chasing partner Joel quits to join another chase team. Undaunted, Reed keeps up the pace until finally he and Tim Samaras face off with a unhappy rain-wrapped tornado. Tim deploys probes and runs for his life, but Reed pushes close to the monster - through downed power-lines - to score the intercept of a lifetime.

Reed, Sean and Tim take on the strongest tornado conditions of the season, a super storm headed right for the Kansas-Missouri border. The dream setup packs country roads, while Mother Nature unleashes a twister in Tim's backyard. Tim gambles and intercepts one of the most dangerous tornadoes he's ever encountered.

Both Tim Samaras and the TIV team face off with a dangerous tornado. Reed pushes too close, and finds no place to hide.

Sean Casey's meteorologists finally put him in position for the shot of a lifetime, and this time it's a home run. Reed, Tim, and Josh all score big.

On the last chase of the season in Nebraska, Reed and Tim chase multiple vortices. But when an EF-3 monster touches down right on top of Reed's armored research vehicle, Mother Nature shows who really dominates in Tornado Alley.