https://www.cmoa.jp/title/259078/

The fleeting romance between an unpopular man and a mermaid who came ashore.

Pokémon Trainers Pearl and Diamond are starstruck! Their lifelong dream is to floor an audience with their Pokémon comedy act. So how do they wind up as bodyguards to a pampered little rich girl on a quest to reach the peak of Mt. Coronet...?! Come along and join the thrills and laughs as Pokémon Adventures continues! Plus, meet Starly, Bidoof, Luxio, Combee, Bronzor, Rotom and many more Sinnoh Pokémon friends! (Source: VIZ Media) *Note: In the Viz Media release, the Diamond & Pearl arc’s volumes were collected under the same title as the Platinum arc; this entry is exclusively for the Diamond & Pearl arc.*

This chapter follows the adventures of Black, who is on a quest to become the Champion of the Pokémon League. He is joined by White, a young woman who owns the Pokémon acting company, the BW Agency, and aims to raise the best Pokémon actor. As they go through the Unova region, they encounter the group Team Plasma, who aim to free Pokémon from Trainers, and the mysterious N. (Source: Bulbapedia)

The chapter follows Gold, who gets in a battle with Arceus, as he searches for the missing Lance. Elsewhere, Team Rocket has resurfaced, which causes Silver to set out and stop them once more. Meanwhile, the Four Generals, Archer, Proton, Petrel, and Ariana have taken over the newly-revived Team Rocket from Carr in attempt to find their currently-missing leader, Giovanni. (Source: Bulbapedia)

This chapter follows the adventures of Blake, a member of the International Police. He searches for members of the villainous group Team Plasma that was defeated in the Black & White chapter. Elsewhere is Whitley, a former member of Team Plasma who has gone in hiding in Aspertia City after the team's defeat in the Black & White chapter. (Source: Bulbapedia)