The Octonauts shipwreck on a desert coast and meet water scientist monkey Paani, who leads them to thirsty animals in need of major hydration.

During a volcanic eruption in Iceland, a volcano begins melting the ice of the glacier sitting on top of it, threatening to flood a valley below and take out 2 reindeer herds unless Dashi, Peso and Paani can evacuate them.

Kwazii sets off to assist Calico Jack in taking a group of bombardier beetles to a new island home, but they have to find the group's scout first, and he is proving difficult to catch.

After a delivery run to ferry supplies to Professor Natquik in Antarctica, Dashi must fly to a tropical island with Peso and Tweak in tow to help Kwazii and Pete rescue Calico Jack from a pile of trees. However, Dashi has to fly through a fierce windstorm first.

Paani loses his soil sampling pole while doing research in Siberia with Professor Inkling. When Dashi and Peso arrive, the group discovers a Siberian Salamander frozen in ice, and after she wakes up, all present are in danger, with underground methane deposits beginning to blow.

Paani rescues a Bailey's snake from a mudflow in the Himalayan Mountains and calls for backup, which arrives in the form of Dashi, Tweak and Tunip in the new Terra-Gup 1. The group now has to find the snake a new hot spring to call home.

After the Nevada desert gets hit by an earthquake from Alaska, Pearl calls for backup to help clear rocks off an algae patch in Devil's Hole so that the pupfish can access their food. Peso, Dashi, and Shellington arrive to help, but the severity of the situation very quickly rises.

Towards the end of their Australian vacation, Dashi and Koshi receive a weather warning and begin evacuating the local area before a flash flood hits. But after helping 2 kangaroos and a bearded dragon, the duo have to find a pregnant desert crab.

Dashi and Paani head off for Antarctica to help Professor Natquik investigate the possibility of running water in Antarctica. However, when a lost skua comes into the picture, Paani and the misplaced seabird have to rely on Natquik and Dashi for a rescue.

Dashi and Min discover a group of Quino Checkerspot caterpillars while mapping a valley, but while the bugs nap until more plantains grow, the 2 must move them and keep them safe with the help of Shellington and Tunip.

Peso's little brother Pinto must return home from his stay with the Octonauts, but while attempting to help Dashi, he becomes distracted, which becomes problematic when both she and Paani get stuck in a boiling sulfur pool in Yellowstone Park.

Paani calls in for backup when a rockslide begins in the Rocky Mountains, which arrives in the form of Barnacles, Tweak, and a few Vegimals in the new Terra-Gup 2. Unfortunately, they have to evacuate some stubborn mountain goats who are not keen on leaving.

Barnacles, Dashi, and the Vegimals set off to help Min relocate a giant panda who just ate up an entire bamboo grove in China. Unfortunately, things get complicated when a second one shows up halfway to the bamboo.

Dashi, Paani, and Tweak follow a developing hurricane to track its direction. When they reveal that the storm is heading for the Florida Everglades, however, the Octo-Ray gets caught in the fierce winds, preventing them from assisting Ranger Marsh.

While the Octonauts are clearing up an island after a tropical storm, the Vegimals attempt to help a misplaced goby return to his home pond. Kwazii soon shows up to help, especially when a hungry bird comes after the goby.

Kwazii joins Tracker in a survival test in the Sahara Desert. However, a young golden mole and Kwazii's misplacement of their supplies mean that they quickly encounter problems when a sandstorm hits.

Paani, Shellington, and Kwazii search New Zealand for a weta in trouble, but after 3 duds discover that the endangered weta is a Tasman Lake Giant Weta, one who is in danger of being eaten by hungry rats.

Paani discovers a nest of dormice that have prematurely woken from their hibernation, but when Shellington and Tweak arrive to help, all three have to hurry before the dormice get caught by a hungry weasel.

While examining the results of coastal erosion on an island's shoreline, Kwazii, Tracker, and Calico Jack have to reunite a Harlequin Duck mother with her wayward nest. Unfortunately, a clever and hungry raven manages to fool Calico Jack and steal an egg.

While on a spelunking expedition in the Hang Son Doong caves, Kwazii, Shellington, and Ryla get trapped when an unexpected rainstorm hits and are trapped with an Indochinese tiger.

Tweak, and Dashi set off to help Ranger Marsh track down a turtle egg that vanished after a swamp fire, narrowing the suspect down to a misplaced nine-banded armadillo.

After Paani gets swept up by a river flood in a rainforest downpour, Dashi and Tweak arrive to check on him and discover a colony of fire ants doing so. Unfortunately, the insects climb onto the Octo-Ray while a bigger storm is approaching.

Peso and Dashi get stranded in the Australian wilderness after the Octo-Ray overheats while cooling off some flying foxes. However, they must hurry to help a flying fox mother and her baby, who is drastically overheating by the minute.

Peso and Tunip are helping to feed a colony's new pufflings while Kwazii tries to fend off a seagull until Barnacles returns with some missing puffins.

While responding to Paani after losing contact with him, Peso, Tweak, and Tunip have to stay with him until a lightning storm passes so Dashi can pick them up. Unfortunately, Tunip gets stuck in a landslide, but the others receive help in the form of a neighboring giant pangolin.