Here’s the right order in which to watch the Sailor Moon franchise
In Season 1, Usagi discovers her Sailor Moon powers through a talking black cat. She helps unlock the powers of four inner guardians, so named because they are the guardians of the inner planets of the solar system. She also meets Mamoru Chiba and his superheroic alter ego, Tuxedo Mask, as the group take on the Dark Realm.
In “Sailor Moon”, the first arc sees Usagi fighting off the attacks of Queen Beryl’s henchman, Jadeite, on her own. Cursed Jewels, Tarot Cards, and Cassettes are just a few of her tools. A mysterious radio station, health club, and pet store are all sites Jadeite uses to steal humanity’s energy for Queen Beryl.
It’s not until episode 8, “Computer School Blues”, that Usagi gains allies (beyond Luna) in her fight. The Talking Cat is suspicious of his classmate Ami Mizuno, who turns out to be Sailor Mercury, another Guardian. She helps Usagi with Jadeite’s latest plan, a clock that drains human energy.
Later, the duo investigate a Shinto priestess, Rei Hino, who appears to have strange powers. At first, Usagi thinks she’s the Moon Princess she’s been looking for, but it turns out she’s another Guardian, Sailor Mars.