Manga Introduction.

The circumstances under which we meet Rei Hino and her subsequent transformation into Sailor Mars in the manga, for the anime version go here.

In the manga, we are first introduced to Rei Hino in Act 3. Sailor Mercury has already been discovered, and so we are overdue for a new main character. The Act begins with Queen Beryl explaining the Silver Imperium Crystal to her minions.

Our first glimpse of Rei she is praying over the fire at her grandfather's shrine where she thinks that she senses evil. This thought it cut short, however, as several children she knows get on a bus and she waves them off. As the children leave they talk about the 6:00 Phantom Bus, at Sendai Hill.

After a brief interlude with Ami and Usagi, Ami mentions that 'a really pretty priestess' is on the same bus as her. A bit of a strange thing to mention perhaps, but, let's go with it shall we? Coincidentally, Rei walks in front of the arcade where Usagi and Ami are hanging out at that precise moment. Usagi is particularly taken with Rei, even going so far as to get off at the same bus stop (Sendai Hill).

Phobos and Deimos (Hino's crow companions) attack Usagi as she gets off the bus, and Rei emerges from the shrine shortly afterward as she senses an evil spirit. She throws a paper charm presumably to exorcize the evil from Usagi. Realizing her mistake quickly, Rei apologizes to Usagi for attacking her.

The conversation between Rei and Usagi is cut short however when the mother of one of the children from earlier in the Act comes to the shrine to pray for her daughter, Mimi who is missing. Mimi got on the bus at Sendai Hill and has not been seen sense. The girl's mother says the place is creepy and, while, at first says it's not the shrine that's creepy whispers to her friend that it is Rei and her family that are. She says people even suspect Rei has ESP.

Despite this, later on, Mimi's mother returns to the shrine to ask Rei to use her ESP to find Mimi. In the meantime several other children have gone missing thanks to the 'Phantom Bus'. Rei apologizes to the woman and her friends saying she cannot always control her ESP. And, of course, being the nice people that they are, get upset when she tells them to go to the police. Rei shouts at them to go home.

Despite denying the request of the people to find their children Rei, goes back to the fire to try and find out what is going on. She has a vision of Usagi and Jadeite, one that gives her a bad feeling. Deciding that if Usagi is in danger she needs to help Rei leaves the shrine. Of course, as luck would have it as she leaves the shrine Rei comes across Jadeite driving the bus, and she becomes unable to control her body. She gets on the bus, where it is presumed that she is knocked unconscious fairly quickly.

As the bus drives away Usagi sees Rei in the window of it, just as the bus vanishes into a black hole, transforming herself into a Stewardess, (for reasons unknown to me) she leaps upon the bus before it disappears completely. While Luna and Mamoru are unable to catch the bus before it vanishes Usagi joins it as it vanishes. Fortunately, due to their communicators, Sailor Mercury is able to join Usagi in the middle of nowhere, though, Luna gives her an extra henshin pen before Mercury leaves.

As Sailor Mercury arrives a scuffle ensues during which Luna tells Mercury to give the spare henshin pen to Rei who transforms into Sailor Mars. Mars makes short work of Jadeite, setting him on fire, before all the Sailor Senshi flee with the kidnapped children. Sailor Mars initially seems surprised that she is the soldier of Mars, but rationalizes it with the fact that she has always had powers.