This episode is based on Act 3 of the manga, which Episode 10 of the anime was based fairly closely on.

The style of adaptation here is similar to that found in Act 2 - the most important point (Rei is Sailor Mars) is kept intact, as are some other general plot ideas: Kids are being sucked into another dimension, angry stupid people think Rei is responsible, and Usagi tries to become friends with Rei but can't.

However, in other ways the episode is very different from its manga and anime counterparts. In the manga (as in the anime, which I'll get into later), people are disappearing when they ride the bus on a cursed bus route. Presumably this would have required too high a budget for PGSM, so instead some girls just go into another dimension at a random point in a forest. Usagi sees Rei and follows her because she is so pretty, which leads her to the Hikawa Shrine. This is as opposed to PGSM, where Usagi bumps into Rei by accident, picks up her bracelet, and goes to the Hikawa Shrine to return it. In the manga, Usagi later uses the transformation pen to turn into a stewardess for no apparent reason, and then gets on the bus to the other dimension, where she and Rei fight Jadeite. Ami and Luna are elsewhere, and help using a computer (although Luna then teleports Ami to where Usagi is). The battle in PGSM involves a really weird looking monster, who shoots vines that can tie the girls up. It also involves Tuxedo Mask (who doesn't appear in this manga chapter) and Sailor Mercury somehow creating a portal into another dimension using her "Mercury Aqua Mist" attack.

Other elements from the manga that were not included in this episode of PGSM include communicator watches that came out of the arcade machine as prizes (in the anime they get communicators later on, and in PGSM they use their Teletia-S cellphones), a cute scene between Usagi and Mamoru on a bus, and some further explanation about the Silver Crystal. Some things that were added in PGSM include a much more interesting way of presenting the exposition (Luna just explained the Sailor Soldiers' mission in the manga, but PGSM had that hilarious quiz show scene) and heavy suspicion that Sailor V could be the Princess.

The anime also changed various things about this story. Usagi and Naru went to the Hikawa Shrine to buy charms, which is how Usagi ended up meeting Rei for the first time. Rei hits Usagi with an ofuda (which is similar to how she almost does so in PGSM), which knocks her out cold. A subplot is added about Jadeite working at the Hikawa Shrine. Sailor Moon and Sailor Mars fight a monster instead of Jadeite, and instead of using a computer to help, Mercury created a portal for Moon and Mars by wishing that everyone was okay (it's funny how Mercury's actions made no sense in any of the three versions, even though she did something totally different in each one). Tuxedo Mask helped out by driving a bus, which towed the other buses through the portal.

Various other anime-original elements were not used in PGSM. Rei's grandfather is a dirty old man in the anime, who hits on the girls who go to the shrine. In the manga he barely appeared and looked very different, and we were never really shown his personality. Also, the anime version of this story introduced Rei's crush on Tuxedo Mask, something that would be very unlikely for the manga Rei, who shows no real interest in men.

The conclusion of this episode is very different in PGSM to in either the manga or the anime. Rei seemed kind of uninterested in being a Sailor Soldier in Act 4 of the manga, but she never actively refused to do it. In the anime, she didn't get on very well with Usagi, but she never let it get in the way of her duty to fight. In contrast, this episode of PGSM ends with Sailor Mars flat out refusing to fight with the other Guardians. This is another sign of PGSM showing more attention to the characters, and allowing them to change over time (even if her reluctance does only last for about half an episode). It's a definite improvement in my opinion. (Rei's dislike of karaoke is, of course, new to PGSM.)

Let's move on to the Dark Kingdom. Jadeite was killed in Act 3 of the manga, but in the anime and PGSM it was a monster sent by him that was killed. In the anime he survived until Episode 13, when there was a big showdown. Nephrite and Zoisite both appeared for the first time in Act 3 of the manga, but their first appearances in the anime were in Episode 13 and Episode 14 respectively. In PGSM, both Nephrite and Zoisite have yet to appear.

Finally, between Mars' introduction (based on Act 3 of the manga) and the Masquerade Ball (based on Act 4 of the manga), the anime added lots of filler. This included the silly subplot about Mamoru and Rei dating (although it mainly seemed to be Rei forcing Mamoru to go on dates with her), and Nephrite disguising himself as a civilian called Masato Sanjouin, who Naru falls in love with. Also, as I mentioned in the Act 1 comparison, the anime has Mamoru not initially know that he is Tuxedo Mask. He magically transforms without even realising it himself, as we are shown in Episode 19. Mamoru gradually figures it out. All of this is amid various monster-of-the-week episodes, and none of this is present in PGSM.