1. INTRODUCTION This article explores various lessons to be drawn from Cook v. Lewis, (1) a case of seemingly lasting interest and, in so doing, will mimic the economy of exposition that is a hallmark of its reasons for decision. The case is an early example of the jurisprudence of the Supreme Court of Canada acting as our court of last resort. It reveals the importance of the drawing of pleadings and how plaintiffs can thereby gain advantages. It reviews the choices available to an aggrieved party faced with multiple defendants. It is a singular example of a reversed burden, not just evidentiary but of the legal onus itself. The obiter dicta in Cook v. Lewis foresaw development of liability attaching to inherently dangerous activities; it pointed the way to the very recent developments of liability based on destruction of the plaintiff's proof and, some would find, the origins of the duty to warn.