Whales, dolphins, killer whales, sea lions and elephants are the main characters of the series. Four, fully-independent episodes of 50-minute duration each, deal with this topic in detail, paying close attention to the species that live in the Argentinean territory:

Returning to the origins: it describes the appearance of life on Earth, and especially the evolution, diversification and conservation of sea mammals.

A step towards the sea: it thematically develops the group called 'Pinnípedos' formed by the sea lions and elephants. Their biology, adaptation, behaviour and ecology.

A sea with dolphins: The dolphins and the killer whales. The different species and their main aspects. Communication and general biology.

The last giants: this episode deals with the big whales, and especially the Great Right Whale.
The mother-baby relationship, communication, conservation and special characteristics.