MOSCOW (AP) _ The cinematic shocker this season is an allegory of Stalin terror and its effects 50 years later. It is believed to be the first Soviet film about the dictator's brutality and was delayed by censors for two years.

''I've never seen anything like it in my life,'' a middle-aged Moscow woman said Wednesday. ''You can't say it's a good film, it's just stunning.''

A woman too young to remember Josef Stalin shuddered and said: ''It's terrifying.''

The movie is called ''Pokayaniye'' (Confession) and was made for television in Georgia, Stalin's native republic. It opened this month in Tbilisi, capital of the republic, and a Western visitor said it was the talk of the town.

It also has been shown to groups of intellectuals in Moscow, including the artists' society on Wednesday.

Neither Stalin nor his feared chief of secret police, Lavrenti Beria, is mentioned by name, but no Soviet audience could mistake the subject and final message that the country has yet to address Stalinism and its consequences.

Director Tengiz Abuladze uses costumes and surrealism in the 2 1/2 -hour film to create an atmosphere that has the effect of setting the action apart from the Soviet Union of the 1930s and the 1980s. His purpose probably was to get around censors, who might have objected to a more direct approach.

Soviet creative arts have undergone some liberalization since Mikhail S. Gorbachev came to power in March 1985. The new leadership of the national film makers' union, elected at a congress last summer, has released several movies from the censor's shelf but nothing so stunning as ''Confession.''

It took 30 years for the film to be made.

Nikita S. Khrushchev denounced Stalin in 1956, three years after his death, and the dictator's name disappeared from public places. His body was removed from the Lenin Mausoleum on Red Square and buried at the Kremlin wall.

''Confession'' opens in a Georgian kitchen. A middle-aged woman is baking cakes.

After she reads of the death of a party official named Varlan, who resembles Beria, the action switches to Varlan's burial and ensuing events.

His body is dug up three times and deposited in his family's garden. The grave robber is caught and turns out to be the woman who was baking cakes.

She defends herself at the trial by recalling her childhood under the rule of Varlan, a figure clad in black with a Hitler moustache and Beria's pince- nez and bulging neck.

Varlan befriends the girl's father, an artist who arouses suspicion when he demands an electric power station be removed from a church converted by the atheist government.

He is arrested and taken away. His wife and daughter join many other women anxiously awaiting news of vanished relatives, but an impersonal voice intones: ''Transferred. No address.''

A demented woman screams, ''Just tell me he is dead 3/8 Tell me he is dead 3/8''

The frantic heroine and her mother hear that names and addresses of prisoners are etched on logs at the railway station. They inspect the logs in vain.

Another woman, finding her relative's address, caresses it as she would a child. The girl plays with wood shavings as she watches a machine make pulp of the logs that have come to symbolize the prisoners.

A surreal court complete with blindfolded woman holding the scales of justice then is shown judging her father.

After other friends disappear, the girl's mother is seized. The flashback ends with the screams of the women as they are separated.

Back in the present, the woman tells the court she will dig Varlan up again if she is freed, because ''to bury him is to hide what he did.''

Varlan's son, frightened by the disclosures, tries to have her committed to a mental hospital. The son's own son, symbolic of Soviet youth who know little of Stalin's terror, is horrified by what his grandfather did.

''Times were different then, it was a difficult time,'' his father says. ''Your grandfather never killed anyone with his own hands.''

The grandson commits suicide. His father exhumes Varlan's body and hurls it into a ravine.

At the end comes the revelation that all the action has been a fantasy of the cake baker and society still has not dealt with Stalinism.