From Bulbapedia, the community-driven Pokémon encyclopedia.
Platinum Berlitz (Japanese: プラチナ・ベルリッツ Platinum Berlitz) is the female main character for the Pokémon Diamond & Pearl chapter and the Platinum chapter story arcs of Pokémon Adventures. At first, she was only known by her family name as her given name matches the third version of the fourth generation games; Pokémon Platinum.
Platinum is a member of the house of Berlitz, a 200-year old and extremely financially powerful family of Sinnoh. She wears diamond and pearl rings. She does not give her name to commoners, instead insisting that they refer to her as Missy (Japanese: お嬢様 Ojōsama, a term used to refer to the daughter of someone of high class).
The Berlitz family tradition is for members coming of age to travel to the peak of Mt. Coronet to obtain materials to make their personal family crest. At the suggestion of the Berlitz's butler, Sebastian, her father hired two bodyguards to protect her in her journey. Professor Rowan provided her with three Pokédexes, three Pokétches, and the three Sinnoh starter Pokémon so that Platinum would share them with her bodyguards to assist him in his research.
However, because Diamond and Pearl coincidentally match the bodyguards' description--one in a red scarf and the other in a green scarf--Platinum presumes they are her bodyguards instead, and the duo think that this journey is a sort of reality TV show. Platinum assumed that they were actually her bodyguards, chosen so the trio would not seem odd.
Platinum is amazed by the closeness of Pearl and Diamond, as well as their various skills: Pearl's assortment of battling advice and Diamond's ability to cook Poffins and instincts on Pokémon. She also is an audience for their various Manzai attempts and is amused by them at times. Platinum often can be demanding of Pearl, annoying him. Platinum is also unaware of a crush Diamond has on her.
Platinum is very knowledgeable as a result of reading lots of books during her childhood. However, since beginning her journey she has decided that it is better to actually experience as much as possible. For this reason, Platinum challenges the Gyms of Sinnoh and also takes on other challenges such as the Super Contests of Hearthome City. She has shown a natural tendency to recognize patterns and has an almost encyclopedic knowledge of various areas of Sinnoh and Pokémon in general, although towards the beginning of her journey, she had difficulty dealing with wild Pokémon.
Later on, Platinum receives Steven Stone's Villa in the Resort Area and travels to the Battleground. There, she meets up with Looker, who escorts her to the Battle Frontier as part of his ongoing investigation into Team Galactic.
It seems that, after saving her from Team Galactic, Platinum gains respect for Diamond and Pearl, by calling them by their first names, but, she still refuses to give her name. The boys assume her name is "Missy", hearing it from Pearl's Chatot, who repeated it from a conversation between Platinum and her butler. She revealed her name to them after formally accepting them as her bodyguards and friends.
- In the beginning of the Diamond & Pearl chapter of Pokémon Adventures, there were some moments where Platinum's first name was actually said, but her first name was always covered by another's speech bubble (to show that it's drowned out by that person's speech). For example, when facing the gym leader Maylene, she is announced as the challenger, but yells when her name is said, so that her first name is unheard. The writers were most likely waiting for the release of Pokémon Platinum to name her for it.
- Platinum is one of three Pokédex holders to have a known last name, the other two are Blue and Sapphire.
- Out of the three, she is the only one not to share her last name with an in-game professor, as she is not related to one.
- Three of Platinum's Pokémon are in the same evolutionary family as Dawn's Pokémon, though unlike Platinum, Dawn's are still in their unevolved state, though one, Pachirisu, doesn't evolve.
- She also had a Mamoswine at one point, though she gave it it to Diamond without ever being shown using it.