Cheburashka was the beloved misfit of Soviet animation. It’s now a missing treasure for Russia.

MOSCOW — The best-loved soundtrack of Soviet-era childhood rang with melancholy about the lost past and the unfortunate fact that birthdays come only once a year. Its star was an animated outsider — a fuzzy, large-eared "creature unknown to science" — named Cheburashka.

The endearing Cheburashka became a cultural icon with serious star power — chosen as Russia’s Olympic mascot four times and still beloved for story plots full of his naive optimism and poignant efforts to belong in Soviet life.