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.

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.

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.

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.

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.

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

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.