If you loved Detective Conan Drama Special 1: The Letter of Challenge, try Gamera vs. Jiger
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.
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Detective Conan Drama Special 1: The Letter of Challenge
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Gamera vs. Jiger
What Gamera vs. Jiger is
A family-friendly monster mash for the discerning giant-turtle fan. Jiger arrives in Japan after some meddling with a Wester Island statue. Gamera takes on this new foe, but ends up needing a submarine extraction performed by two precocious children. Mission accomplished, sort of.