の仕業だ

is the work of

→ の
phrase Uncommon #13,213
is the work of Often used to attribute an act or incident to someone, especially when expressing suspicion or blame.
JA: この騒ぎは誰の仕業だ?
EN: Who’s behind this commotion?

幹也それ誰の仕業だ

Mikiya, who did that?

— The Garden of Sinners: Paradox Spiral (2008)

鉄雄を変えたのもお前の仕業だな!

You’re the one who changed Tetsuo too!

— AKIRA (1988)

ミリシアの仕業だと言ったのか

Did you say it was the militia's doing?

— エリート・スクワッド ブラジル特殊部隊BOPE (2010)

恐らく、トムの仕業だよ。

It was probably Tom’s doing.

誰の仕業だ?

Who did this?

— デッド・ドント・ダイ (2019)

いつもの野蛮人どもの仕業だ

The work of those savages as usual.

— ライフ・イズ・ビューティフル (1997)

弟のラモンの仕業だ

It was my younger brother Ramon.

— 荒野の用心棒 (1964)

ゾンビの仕業だと?

You mean zombies did it?

— デッド・ドント・ダイ (2019)

ヘルマンの仕業だな

This is Hermann’s doing.

— 嵐の中で (2018)

誰の仕業だと?

Whose doing do you think this was?

— ウィッチ (2016)