If you loved Operation Y and Other Shurik's Adventures, try The Secret of the Third Planet
A bridge between a film you've already seen and one most people haven't. The Secret of the Third Planet has roughly 4.3× fewer votes than Operation Y and Other Shurik's Adventures — it's a deeper cut, not a mainstream recommendation. Here's what they share, and what the second one does that the first one doesn't.
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The Secret of the Third Planet
What The Secret of the Third Planet is
Observant explorers of the 22nd century set off collecting cosmic fauna for Moscow Zoo, unaware their cargo of a chatty bird carries the key to a shadowy plot. Along the way they dodge a villain aiming to silence the legendary Two Captains but can’t outrun a squawking sidekick who knows too much. A feathered MacGuffin saves the day, though the story’s niche ambitions never quite fill the big screen.