They travel through black holes to complete Alien's missions, and encounter various dangers on the spaceship and on the planets they visit.
Peo's wife, Ulla, has disappeared and he asks Mira, Glen, and Henrik to accompany him into space to try to find her.
In the series they also meet new characters, among them Irina Teresjkova (who had been beamed up in 1963 from her "Sputnik 1"), Benke Bengtsson, and Gaia and Garsson, who work at a "rymdmack" ("space filling station").
The new characters are played by Jonas Sykfont (Femman/Benke Bengtsson/Garsson), Ingela Schale (Irina) and Inga Sarri (Gaia).
Mira (Philoméne Grandin) has now become mother to the 13-year-old girl Billie (Fanny Ketter) and they have created a good life for themselves on Earth.
Peo's (Anders Linder) and Ulla's (Christina Göransson) time as "Gaior" is soon up, and the calm at Milky Way ("Vintergatan") comes to an end.
Ulla disappears again and the worried Peo sends the cargo ship's pilot Pax (Sanna Persson Halapi) to Earth to fetch Mira, who he thinks can help him.
Around the time when Pax returns to the space station, Peo has narrowly escaped being murdered by the "fun" Captain Storm (Per-Axel Gjöres) who works for the "Triumvirate" of Professor (Eva Westerling), Lennartsson (André Wickström) and Greven (Anders Jansson).