на вас нашло

what's gotten into you

→ на
phrase Rare #41,868
what's gotten into you A colloquial expression used when someone is behaving unusually or irrationally. Literally, “what came over you.”
RU: Что на вас нашло? Вы обычно так не говорите.
EN: What's gotten into you? You don't usually talk like that.

Не знаю, что на вас нашло.

I don’t know what came over you.

Что на вас нашло?

What's gotten into you?

Что это на вас нашло?

What came over you?

— Академия Рашмор (1998)

Я не знаю, что на вас нашло.

I don't know what's gotten into you.