今回紹介するのはタイトルのとおり
ringleader
意味：首謀者・主犯格
です。
不正や犯罪を行うときのリーダー格を指す言葉なので、
仕事やプロジェクトのリーダーに対しては使えません。
最初の使用例は「Person of Interest」から
Finch: Where the hell have you–
John: There’s no time. We were wrong. Hansen isn’t the target. She’s the ringleader. They’re going after Wheeler. Tonight.
次の例は「キャッスル」から。
Beckett : The ringleader was Robert Kincaid, former bond trader. He’s the one who planned the entire operation. The economy might have collapsed, but he was still gonna get his payday. Most of them were ex-Wallstreeters.
次の使用例は「Boston Legal」から。
Denny Crane: He is leaning casually against the banister in front of the jury. Michael was always the ringleader. Always the one to take matters into his own hands. And he’s the one that did so here.