High above West 52nd Street on a muggy Midtown afternoon, Marty Lipton picks up my pitch document: an invitation to contribute a chapter in a new M&A book. The most fleeting of glimpses and it’s tossed disdainfully back across his desk. “Not interested,” barks the biggest rainmaker at the world’s most profitable large law firm, Wachtell Lipton Rosen & Katz. “You’ve got half an hour – what else do you wanna know?”

Hurriedly reverting to interview mode, my questions focus on Wachtell’s evolution, innovation and pre-eminence as a New York transactional powerhouse.