I'm embarrassed to admit that I didn't want to watch this one when I first came across it many years ago, just because I thought it looked too different from the original Dr. Seuss art style. Boy, was that a mistake! This is a great adaptation, even if it's not entirely faithful (for example, Thing One and Thing Two are missing - but, at least for my part, are not missed).

The art direction is great. The bright colours, strong lines and psychedelicism reminds me of Ugarov's Music Box with a Secret, while the character design and constant transformations reminds me of Saakyants' The Fox Who Couldn't Do Anything (both from 1976). It was done by Aleksandr Petrov before he felt he found his true voice as an artist. That came later that year on Night, directed by Vladimir Petkevich (who worked as an animator on this one).

I think it may also have been the first-ever Russian Dr. Seuss adaptation. At the time, Dr. Seuss was almost unknown in the Russian-speaking world, and Karayev only discovered him through the large collection of English-language children's books owned by the family of the famous children's writer Chukovsky. Karayev would go on to direct 3 more Dr. Seuss adaptations before (I'm guessing, but it's not unlikely) more stringent copyright enforcement on unlicensed adaptations by Western firms in the 1990s made it impossible to make any more. The one he made 2 years later, Welcome!, might be even better, although it's a close call.

The Animation Stories blog wrote a short review back in 2015, writing: "The theme of escaping into a land of fantasy from boredom of home or school is rather typical for the Soviet cartoons of the era of Stagnation, so Cat in Hat (Cap), with its protagonist, a safe entertainer who does not forget to clean the room before children's tired mother returns from work, falls perfectly within the scope of Soviet cartoons of that time."

Certainly the screenplay would have raised no concerns - it falls squarely into the broad, encouraged category of "stories that make children learn to be better people". I'm not sure if "escaping into a land of fantasy from boredom" was that common of a theme, though. I can think of Ara, bara, puch! (1986) by Vladimir Pekar, and Time Out (1984) by Priit Parn, but both of those are edging into the Perestroika era already, rather than the so-called "Stagnation" (as is true of this one, too). If you're really stretching, you might include Anatoliy Petrov's And Mama Will Forgive Me (1976), but boredom is really not the dominant theme of that one. I suppose you could also include Music Box with a Secret (1976), but again, boredom is not the reason for the escape into fantasy there. Well, I suppose Ugarov's At the Back of the Class series (1978-1985) also generally fits.