hook, line and sinker

Completely; (of belief or acceptance) naively or unquestioningly.

Japanese Meaning

完全に、全く疑うことなく受け入れる / 丸投げ、全てをそのまま信じる

He fell for the prank hook, line and sinker.

彼はそのいたずらにすっかりだまされた。

Sense（1）

Completely; (of belief or acceptance) naively or unquestioningly.

I told him you were just a friend, and he fell for it hook, line and sinker.

hook

（ canonical ）

line and sinker

（ canonical ）