After the murder of Sergei Kirov on 1 December 1934 (which served as one of the triggers for the Great Purge of the Soviet Communist Party), Zinoviev, Kamenev and their closest associates were once again expelled from the party and arrested in December 1934.
They were tried in January 1935 and were forced to admit "moral complicity" in Kirov's assassination.
Zinoviev was sentenced to 10 years in prison and his supporters to various prison terms.

In August 1936, after months of careful preparations and rehearsals in secret police prisons, Zinoviev, Kamenev and 14 others, mostly Old Bolsheviks, were put on trial again.
This time, the charges included forming a terrorist organization that supposedly killed Kirov and tried to kill Stalin and other leaders of the Soviet government.
This Trial of the Sixteen (or the trial of the "Trotskyite-Zinovievite Terrorist Center") was the first Moscow Show Trial and set the stage for subsequent show trials where Old Bolsheviks confessed to increasingly elaborate and egregious crimes, including espionage, poisoning, and sabotage.
Zinoviev and the other defendants were found guilty on 24 August 1936.

Before the trial, Zinoviev and Kamenev had agreed to plead guilty to the false charges on the condition that they not be executed, a condition that Stalin accepted, stating: "that goes without saying".
Nonetheless, a few hours after their conviction, Stalin ordered their execution that night.
Shortly after midnight, on the morning of 25 August, Zinoviev and Kamenev were executed by shooting.

Accounts of Zinoviev's execution vary, with some having him beg and plead for his life, prompting the stoic Kamenev to tell Zinoviev to "quiet down and die with dignity."
Regardless, Zinoviev put up such resistance to the guards that, instead of taking him to the appointed execution room, the guards took him into a nearby cell and shot him there.

The execution of Zinoviev, Kamenev and their associates was a sensational news event in the USSR and around the world, paving the way for the mass arrests and executions of the terror of 1937–1938.
In 1988, during perestroika, the Soviet government formally absolved Zinoviev and his co-defendants of the spurious charges which led to their deaths.
After the murder of Sergei Kirov on 1 December 1934 (which served as one of the triggers for the Great Purge of the Soviet Communist Party), Zinoviev, Kamenev and their closest associates were once again expelled from the party and arrested in December 1934. They were tried in January 1935 and were forced to admit "moral complicity" in Kirov's assassination. Zinoviev was sentenced to 10 years in prison and his supporters to various prison terms.
In August 1936, after months of careful preparations and rehearsals in secret police prisons, Zinoviev, Kamenev and 14 others, mostly Old Bolsheviks, were put on trial again. This time, the charges included forming a terrorist organization that supposedly killed Kirov and tried to kill Stalin and other leaders of the Soviet government. This Trial of the Sixteen (or the trial of the "Trotskyite-Zinovievite Terrorist Center") was the first Moscow Show Trial and set the stage for subsequent show trials where Old Bolsheviks confessed to increasingly elaborate and egregious crimes, including espionage, poisoning, and sabotage. Zinoviev and the other defendants were found guilty on 24 August 1936.
Before the trial, Zinoviev and Kamenev had agreed to plead guilty to the false charges on the condition that they not be executed, a condition that Stalin accepted, stating: "that goes without saying". Nonetheless, a few hours after their conviction, Stalin ordered their execution that night. Shortly after midnight, on the morning of 25 August, Zinoviev and Kamenev were executed by shooting.
Accounts of Zinoviev's execution vary, with some having him beg and plead for his life, prompting the stoic Kamenev to tell Zinoviev to "quiet down and die with dignity." Regardless, Zinoviev put up such resistance to the guards that, instead of taking him to the appointed execution room, the guards took him into a nearby cell and shot him there.
The execution of Zinoviev, Kamenev and their associates was a sensational news event in the USSR and around the world, paving the way for the mass arrests and executions of the terror of 1937–1938. In 1988, during perestroika, the Soviet government formally absolved Zinoviev and his co-defendants of the spurious charges which led to their deaths.
Grigory Zinoviev