The Octonauts, consisting of the Octopod crew and captain, are the recurring main characters.
Original main characters These are the Octonauts that were in the original series, including the captain. They are unchanged in
Above & Beyond, with the exception of the
Vegimals, who are voiced by
Kate Harbour. Everyone's previous actors from the original series reprise their roles here. •
Barnacles (voiced by
Simon Greenall; singing voice provided by Ross Breen) is a polar bear who is the captain of the Octonauts. He is skilled in piloting many vehicle and is strong enough to lift a
giant clam. In the episode "The Caves of Sac Actun", it is revealed that Barnacles is
claustrophobic. •
Kwazii (voiced by
Rob Rackstraw) is a cat
lieutenant and
cryptozoologist who speaks in a
Cockney accent. Kwazii is a daredevil cat with a mysterious pirate past. He believes in many
sea monsters such as the Nackerwhack, Tri-Toothed-Terror, Giant Shrimp Monster and Monster of Creepy Cove. •
Peso (voiced by Paul Panting in the British version,
Wayne Grayson in the American version) is a
penguin with a British accent (Spanish accent in the US version) and the
medic of the Octonauts. He is not fond of scary situations, but steps up if someone is hurt or in trouble. •
Professor Inkling (voiced by
Keith Wickham) is a
dumbo octopus who speaks in a posh accent. Inkling is an
oceanographer and assembled the Octonauts to study the oceans. •
Dr. Shellington (voiced by Keith Wickham) is a
sea otter who speaks with a
Scottish accent. Dr. Shellington is a
biologist who assists the Octonauts on missions. He is not a very good driver and once crashed the GUP-D. •
Tweak (voiced by
Jo Wyatt; Jaimie Kelton in season 1 of the American version) is a
rabbit who speaks with a
Southern-US accent. Tweak works as an engineer and is based in the launch bay, where she created the GUP-X and GUP-S. •
Dashi (voiced by
Teresa Gallagher in the UK version, Mary Murphy in seasons 1–4 of the US version, Jenny Yokobori in "The Caves of Sac Actun"–present of the US version) is a
Dachshund who is the photographer for the Octonauts and takes care of all the computers aboard the Octopod. She is also a professional
surfer. •
Tunip (voiced by Kate Harbour) is a Vegimal who is half-tuna, half-turnip, but has the outward appearance of a
harbour seal mixed with a
turnip. He loves to make
kelp cakes and work in the
greenhouse as the Octonauts' head cook and gardener.
New main characters These are the characters that were added to the Octonauts crew in the series
Above & Beyond. They are known as Octo-Agents, friends of the Octonauts who are stationed all over the world. They are experts and adventurers that assist the Octonauts on their new land missions. All Octonauts and Octo-Agents are able to sound the Octo-Alert via new pieces of equipment called Octo-Watches (except Barnacles, who still has his Octo-Compass, and Tunip). •
Paani (voiced by
Antonio Aakeel) is a
macaque who joins the Octonauts as an Octo-agent in the first episode of
Above and Beyond. He is a
hydrologist who studies how water affects all kinds of beings. He is brave and daring, and also impulsive, similar to Kwazii. He gets off on the wrong foot with Kwazii, though, because Kwazii catches him trying to steal supplies from the team to assist animals affected by a drought. •
Calico Jack (voiced by Rob Rackstraw) is a pirate who is Kwazii's grandfather. He travels with Pete, his
parrot sidekick. •
Marsh (voiced by Keith Wickham) is a rabbit and Tweak's father. He works as a
park ranger and loves to explore swamps. •
Pearl (voiced by Kate Harbour) is a sea otter and Shellington's older sister. She works as a
marine biologist. •
Ryla (voiced by Helen Walsh) is a
wombat and old friend of Dashi who specializes in
cave diving. •
Tracker (voiced by Paul Panting) is a polar bear and Barnacles's former protégé. He is the
radio operator for the Polar Scout Emergency Post in the
Arctic. •
Professor Natquik (voiced by Simon Greenall) is an
Arctic fox and Barnacles's former mentor who specializes in field research. •
Min (voiced by
Chipo Chung) is a red panda who is an old friend of Professor Inkling. She resides in the
Yangtze and specializes in mapmaking. •
Koshi (voiced by Teresa Gallagher) is a Dachshund and Dashi's younger sister who is interested in mysteries. She works as a junior Octo-Agent. •
Pinto (voiced by Teresa Gallagher in the UK version, Jamie Kelton in the US version) is a penguin and Peso's little brother who is a quick thinker. He works as a junior Octo-Agent. •
Selva (voiced by
Elena Saurel) is an iguana who debuted in the third season. Originally living in the
Amazon rainforest, she joined the Octonauts as a
botanist and junior Octo-Agent after encountering Shellington and the Vegimals. •
Bud (voiced by
Alan Marriott) is a
beaver whose family taught Tweak everything she knew as an engineer during her youth. He later joined as Tweak's protege and spent much of his time traveling the world to study engineering in nature. •
Haraka is a
cheetah who specializes in keeping creatures healthy and studies their capabilities. She was introduced in the fifth season. ==Vehicles==