How does the man behind Russia’s most soothing cartoon dog end up with an 18+ horror hit? Leonid Shmelkov’s ‘Restlessness’ strands two travelers in a roadside hotel they can’t escape.

Nepokoy (“Restlessness”), a feature-length art-house animation for adults, is now playing in Russian theaters.

That in itself is news: 18+ animation is a real rarity not only in Russia but worldwide.

Nepokoy has already become a phenomenon: it’s the highest-grossing Russian animated film for adults, the living legend Yuri Norstein has praised it, and its heroine has been turned into a Dymkovo toy, a traditional Russian painted-clay folk figurine.

Nepokoy’s director, Leonid Shmelkov, is known online for his viral animated clips about a dog named Andrei and the dog’s friends.

The feature looks nothing like them: it’s a surreal story about travelers stranded in a mysterious hotel run by the eccentric Madam.

The critic Anton Khitrov explains how to read this puzzle of a film — and why it became a hit.