どこの誰だれ

expression, pronoun

who the heck; just who (is that)?

Emphatic version of 誰, used when the speaker is suspicious, annoyed, or wants to stress that the person's identity is unknown or questionable. Often rhetorical.

• どこの誰だれだか知しらないけど、勝かっ手てに入はいらないで。

  I don't know who the heck you are, but don't come in without permission.

• あんなことを言いうのは、一いっ体たいどこの誰だれなんだ？

  Who on earth would say something like that?