Takeshi, known as Brock, supports Ash and Dawn's journey, arriving in Alamos Town for a Pokémon Contest. When dimensional disturbances erupt from the clash of Dialga and Palkia, he provides essential logistical support and caregiving. Brock aids Nurse Joy in evacuating townspeople to safety as spatial distortions threaten the area.

His practical knowledge surfaces through carrying vital supplies and assisting the group's daily needs. A recurring comedic trait emerges instantly upon meeting local tour guide Alice: he develops romantic interest, prompting his Croagunk to intervene with a Poison Jab attack and drag him away, reflecting their series dynamic.

Brock participates in minor collaborations, operating the Space-Time Towers' musical instrument alongside Dawn and Alice. During the climax, he remains with the evacuation group instead of joining the direct confrontation with the legendary Pokémon. His prior experience as a Gym Leader and Pokémon Breeder informs this supportive, non-combat role throughout the events.