The series starts with a dramatic encounter with the Japanese Whaling fleet. The episode then flashes back to the maiden launching and departure of the vessel from homeport three months earlier. Paul Watson and the Sea Shepherds head back down to Antarctica for what promises to be their most intense anti-whaling campaign yet. However, no sooner does the ship leave port than the ship's Gyro breaks and they hit a massive storm the size of Australia

A huge weather system moves in and the Steve Irwin is forced to take shelter behind a large iceberg. By morning, they are surrounded by ice so thick they can no longer move. The ice begins to push against the aging ship's fragile hull, denting it inwards.

The Sea Shepherd gather intel on the fleet's location, they realize that they are low on fuel. As they weigh whether or not to head back to port, they come across the entire Japanese fleet searching for one of their crewmembers that has fallen overboard.

The Sea Shepherds have come across the entire Japanese fleet searching for one of their crewmembers that fell overboard. Paul orders his crew to stand down, and they agonize over being so close to their target, yet unable to attack.

The Steve Irwin is quarantined in Hobart and the crew anxiously waits to find out if they have been exposed to Anthrax. Finally they get the all clear and 1st mate Peter Brown wastes no time leaving the ship after having quit the campaign.

Surrounded by the Japanese whaling fleet, the Sea Shepherds ready themselves for their biggest day of battle to date on the campaign. Helicopter pilot Chris flies up and confirms the crew's fears - all of the whaling vessels are equipped with LRAD weapons.

Captain Watson is in pursuit of the Nisshin Maru when all three Japanese harpoon ships suddenly appear on out of the fog. The Sea Shepherds are completely outnumbered.

As the Sea Shepherds prepare for their fourth straight day of engagement with the Japanese whaling fleet, Andy and Simon argue with Dan over the best strategy for attack.

Low on fuel, the small boats head toward the Steve Irwin, but in order to get them on board safely, Paul must employ a dangerous military strategy, "The Crazy Ivan," circling at a high speed to try and create calm water for the little boats to return.

The Sea Shepherds shock turns to fury when the Japanese fleet pulls a dead whale onto Nisshin Maru for slaughter. Paul Watson instructs the crew to prepare for battle.

Season Finale.The Sea Shepherds continue to attempt to disrupt the whaling fleet's operations. When the Yushin 3 tries to transfer a dead whale to the Nisshin Maru, Captain Watson maneuvers his ship to block the transfer resulting in a full-speed collision.

The former captain of the Ady Gil goes for a boarding attempt and one of the Sea Shepherd vessels goes dead in the water.

Pete Bethune recounts his experience aboard the Japanese security vessel.

The Sea Shepherds face a difficult 2013 campaign with the Brigitte Bardot and their helicopter unavailable. The fleet introduces a new ship, the Sam Simon. Former captain of the Steve Irwin, Paul Watson, is forced to step down due to an injunction preventing him from coming within 500 yards of Japanese whaling fleet. All four of the fleet's main ships feature a new captain, with Watson serving as an observer. The Steve Irwin remains to coordinate the operation. The Bob Barker is sent to search for the whaling fleet and finally locates the Nisshin Maru near the western edge of the whaling ground. However, they sit helplessly as the Japanese successfully kill and load a whale onto the factory ship. The Sam Simon is sent to search for the bunker ship Sun Laurel and finally locates it along with 2 Japanese whaling ships. They attempt to block the refueling, but fail when the rookie captain pulls away, not willing to risk his crew. After hunting, the Nisshin Maru turns east. Realizing that the factory ship is trying to also refuel, the Sea Shepherds send all their ships to interfere. 30 hours later, the ships prepare for the showdown. The 500-tons Bob Barker blocks the 5000-tons Nisshin Maru by parking right next to the Sun Laurel. The Japanese warns the Bob Barker to move but captain Peter Hammarstedt refuses to comply. The Nisshin Maru then pushes the Bob Barker with their bow, damaging the ship and causing it to list dangerously. After a standoff, the Nisshin Maru backs away while the Sun Laurel abandons the operation. Days later, the whaling fleet leaves for Japan with only 103 kills.

After months of frustration, Sea Shepherd finally find their target - the Nisshin Maru. Now, they must run an eight-mile gauntlet blocked by two harpoon ships aggressively defending their mother ship. The success of the campaign rides on this moment.

With three activists aboard the Japanese security vessel, Capt Paul Watson hopes the media frenzy will force the Shonan Maru 2 to back off. Meanwhile, the crew of the Steve Irwin are plunged into their most violent battle yet.

When a massive target is detected on their radar, Sea Shepherd sends out their new helicopter pilot to ID the mystery vessel. But as the helicopter reaches the limits of its fuel range, it abruptly disappears, crashing into radio silence.

The exhausted crew of the Brigitte Bardot scramble to evacuate the ailing vessel. And Captain Paul Watson goes on the offensive, sending a team to board the heavily armed security vessel: the Shonan Maru.

After engaging the harpoon ships using the small boat teams, Captain Paul Watson makes the call to abandon the harpoon ships and go in search of the factory vessel. After a few hours of sailing, the tables have turned — two harpoon ships begin tailing Sea Shepherd!

The Sea Shepherd's stealth boat, the Ady Gil, launches a sneak attack on the Japanese whaling reconnaissance vessel in an effort to break free of the tail and find the rest of the whaling fleet.

The Sea Shepherds have been relentlessly followed by the whaling reconnaissance vessel for two weeks. They find themselves in a full-on engagement on the high seas as Captain Paul Watson orders a massive butyric acid bottle attack on his nemesis.

The Bob Barker desperately searches for their two small boat crews who were lost at sea in the aftermath of a daring mission. Meanwhile, the Gojira locates the whalers' refueling vessel and Locky plays a dangerous game of "chicken" with the massive ship.

As the Sea Shepherds approach the Nisshin Maru, they are suddenly surrounded by four whaling vessels. Suddenly, one of the Japanese vessels moves in dangerously close, and as the deck crew quickly braces themselves, the ships violently collide.

As the first leg of their campaign comes to a close, the Sea Shepherds battle physical and mental exhaustion, especially pilot Chris Aultman. Thanks to an anonymous tip, the Steve Irwin finally locates the whalers' factory ship, the Nisshin Maru.

After nearly a month of searching, the Sea Shepherds have finally found their ultimate target: the world's only whale factory ship, the Nisshin Maru.