At the bottom of the world, a collision has just devastated one of the Sea Shepherds' vessels. The crew on the other vessel stand helpless on their deck, watching in horror as the Japanese vessel barrels through the Sea Shepherds' prized speedboat.

The whalers attempt to lose their attackers in an ice field.

In the aftermath of the devastating loss of their stealth vessel, the Sea Shepherds have returned to the campaign with renewed passion and intensity. Now the two remaining ships are back on the hunt for the Japanese fleet.

The whalers face new attacks from the Sea Shepherds as they mount an attack with both the Bob Barker and Steve Irwin.

The Sea Shepherds embark on another dangerous campaign as whaling season begins in the Antarctic; a donation from former game-show host Bob Barker allows the group to purchase a former Norwegian whaling 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.

With low oil and drinking water, and a damaged helicopter, the Sea Shepherds' hunt for the Japanese whaling fleet has been brought to a halt. While on their way back to port, the radar shows two colossal storms that they can't avoid.

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

The Sea Shepherds depart on their 2010/2011 ant-whaling campaign with a new, fast interceptor vessel. Early on, they find two harpoon ships before the whaling fleet has killed a single whale. Could they be set up for their most successful campaign ever?

When damage happens to one of the small boats, and the Bob Barker is five hours away, the crew realizes that they will have to spend a night at sea. But the crew is wet and freezing already, and early symptoms of hypothermia begin to set in.

New Zealand's Navy contacts the Steve Irwin to respond to an emergency distress signal where five crew members from a Norwegian sailboat have gone missing. Now the Sea Shepherds must risk their lives in a dangerous mission to find the missing mariners.

In the fourth-season finale, Watson claims a major victory after 30 years of fighting, while he and the crew reaffirm their commitment to stopping the whaling fleet.

A plan to intercept the whaling fleet before it reaches the whaling grounds is nearing a critical point. The new helicopter pilot, Gary, spots a ship on the horizon; If it is the whalers' factory ship, this may be Sea Sheparhd's the earliest victory ever.

In the Season 5 premiere, the Sea Shepherd Conservation Society responds to Japan's 2011 announcement to resume its whaling operations in the Antarctic and the government's promise to beef up the fleet's security.

A Japanese reconnaissance ship pursues the Steve Irwin; two members of the Andy Gil crew suffer illness and injury; the Bob Barker's engine fails two days into its journey.

The Sea Shepherds finally locate the factory vessel after months of searching, but it promptly tries to evade the Gojira.

With the Japanese fleet's security vessel looming on the horizon, the captain of the badly damaged Brigitte Bardot orders his crew to evacuate the boat. Meanwhile, in Antarctica, the Bob Barker deploys the small boats team to disable a harpoon ship.

Tailed by a harpoon ship, the Steve Irwin enlists the help of the Sea Shepherds' new, fast interceptor ship in an attempt to break free. Meanwhile, the Bob Barker crew spots a large blip on their radar and believe it could be their ultimate target: the Nisshin Maru.

The Bob Barker and Gojira launch an ambitious assault on the harpoon ship that has been following them and manage to completely disable the whaling vessel. Now free of its tail, the Barker continues searching for their ultimate target, 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.

The Sea Shepherds refuse to be bullied by the Japanese fleet even though they're out numbered. The deckhands repel over the side of the ship to assess the damage from the collision and realize that there is a gash in the steel hull and water is pouring in.

The Sea Shepherds' scout vessel, the Brigitte Bardot is damaged by a 30-foot wave, and help is more than 20 hours away.

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.

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.