のは 君

it's you who…

→ の
phrase Rare #22,072
it's you who… のは marks the preceding action or thing as the topic, and 君 means “you.” Together, they can emphasize that you are the person involved.
JA: パーティーに誘ったのは 君だろ。
EN: You're the one who invited me to the party, right?

消えるのは君だ

You're the one who's going to disappear.

— ロード・オブ・ザ・リング/王の帰還 (2003)

私たちは会えば絶対すぐに分かる私に入ってたのは君なんだって

If we meet, I’ll know right away—it was you who was inside me all along.

— 君の名は。 (2016)

警戒するのは君を守るためだ

I'm being cautious to protect you.

— 灼熱の魂 (2010)

パーティーに誘ったのは君だろ

You're the one who invited me to the party, aren't you?

— Hoje Eu Quero Voltar Sozinho (2014)

あなただけでね執筆の時間が欲しいのは君と同じだ

You’re not the only one—I want time to write, too.

— 落下の解剖学 (2023)

電話に出なかったのは君の方だ

You were the one who didn't answer the phone.

— Hoje Eu Quero Voltar Sozinho (2014)

“平和を”平和が必要なのは君だよアール

“Peace?” You’re the one who needs peace, Earl.

— マルコムX (1992)

いえ説明するのは君のほうですよ!

No, you're the one who needs to explain!

— ライフ・イズ・ビューティフル (1997)