I don't know anything about that - A sneaky way of telling someone they're clueless and you're

A sneaky way of telling someone they're clueless and you're not going to let them get away with it.

'I don't know anything about that' said when your brother said he could speak 10 languages.

'I don't know anything about that' after your friend claimed he could fix your computer with a rubber chicken.

'I don't know anything about that' when your dad said he could bench press a cow.