If you loved Detective Conan: Love Story at Police Headquarters ~Wedding Eve~, try Detective Conan: The Scarlet Alibi
A bridge between a film you've already seen and one most people haven't. Here's what they share, and what the second one does that the first one doesn't.
You already loved

Detective Conan: Love Story at Police Headquarters ~Wedding Eve~
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Detective Conan: The Scarlet Alibi
What they share
Both films are directed by Shunsuke Ishihara, and they sit in Animation / Drama territory. If that's the register that drew you to Detective Conan: Love Story at Police Headquarters ~Wedding Eve~, the second film will land in a comparable space — through a different lens.
What Detective Conan: The Scarlet Alibi is
Tokyo streets at dusk a siren blares Akai family tied to a complex web A classic whodunit from 90s anime era