Case Closed: Conan and Kid and Crystal Mother is a oVA anime that premiered in winter 2004.

About the production: the story comes from a manga, there is 1 episode of about 25 minutes and its current status is "finished".

Its main genres are adventure and mystery, with themes such as Trains, Male Protagonist, Shounen and Age Regression.

On AniList, Case Closed: Conan and Kid and Crystal Mother has an average score of 71%, a good score, and appears on 4,706 users' lists.

Kaito and Aoko are traveling on a train along with Aoko`s father, Inspector Nakamori, in attempts to help stop Kaitou KID from stealing a precious gem known as Crystal Mother. Little do Aoko and Inspector Nakamori know that Kaito is Kaitou KID and he will do whatever it takes to retrieve the gem. Unfortunately for Kaito, he is also being followed by Conan and a little boy named Philip who will do anything to stop him. (Source: Anime News Network)

Official synopsis from AniList.