In stories, or at least in the ones I loved as a child, magical objects appear when a lamp is polished, or a certain word is uttered, or a ring is rubbed. The end result is the same; something wonderful suddenly appears from nowhere. I am sitting in the lobby of a south Dublin hotel and looking in amazement at a fabulous treasure that has materialised unexpectedly out of the most modest of origins: a crinkled plastic supermarket bag. Mark Leslie, son of the late German-born actor and singer Agnes Bernelle, is the person who has created this sleight of...