Khrushchev was giving a speech when a heckler in the audience shouted "Why did you never speak out against Stalin?"
Straight away Khrushchev bellowed “WHO SAID THAT?” and there was a rattle of safeties being taken off by his bodyguards. Nobody spoke. Khrushchev bellowed even louder “WHO. SAID. THAT?!“. He gave a signal, one gesture of his hand. More armed men filed into the hall and stared intently down every row. Not one person moved a single muscle. Dead silence. And after a full minute, Khrushchev said:
“…That’s why I never spoke out against Stalin.”