Called "one of Russia's best-loved actors",[1] he also provided the voice for many Soviet cartoon characters, including Vinny Pukh (Winnie-the-Pooh).

[2] While growing up in a typical Moscow family, he dreamed of becoming a war-plane pilot, which was a very common desire of many boys of the World War II period.

He later became Georgiy Daneliya's regular, appearing in all of his features, including Gentlemen of Fortune, Autumn Marathon, Mimino, Afonya and Kin-dza-dza!.

According to the Allmovie, "his short, round stature, expressive eyes, broad and open face, slow movements, and slightly slurred speech made him ideal for the comic roles in which he specialized".

Many notable actors were said to avoid appearing in the same films with Leonov, for his natural manner of acting made them seem strained.

He gave a hilarious portrayal of a simple, nosey man who drank too much and who adored nothing more than talking nonsense as long as anyone could stand it.

His life was saved only after major surgery and Leonov recovered – only to begin a schedule of performances at the Lenkom Theatre.

But I shall never forget the famous artists of past years, my teachers: Diky, Mikhail Chekhov, the young Simonov, Pevtsov, Rusinova, Vakhtangov, Gritsenko and Yakovlev.

At that time people played cordiality, kindness, laughing through tears and leaving a bit of their heart on the stage.

[1] When his death was announced in the auditorium, the audience spontaneously flooded into the church across the road and lit candles in mourning.