In bafflement, Digby looked briefly at the card the tramp produced from the inside pocket of his greatcoat and waved it away, all his attention on the lean, handsome face sparkling with impish good humour. “Mr. Coward? Well, I’ll be damned! You are a surprise! But, er—no, your suspicions are well founded. He wouldn’t be. In fact, the words ‘kind’ and ‘Rendlesham’ in close proximity would curdle a sentence. But how do you do, sir? We’re to perform introductions later, so for the moment, I’ll be your soul-shifting Hermes. I’m rather charmed by the idea! I’ll just say, I’m delighted that you could manage to get along at such short notice for our little soirée.” And as the nearest cracked college bell started to bang out six: “Right on time! Well done! So, er . . . this way.”

He was beginning to recover from his surprise and, heartened by the familiarity of the man’s tone of voice, which much resembled that of his old housemaster, Digby felt confident enough to hazard a jest of his own. “But first—obol, sir?” He held out a hand, palm up, with a winsome smile. “I believe there is a fee for crossing the River Styx, though nothing more alarming than a raging gutter separates us from our dinner. The ditches are in full spring spate this evening, you’ll find.”

The man grinned and pressed a shining shilling coin into Digby’s hand. “Sorry, no obol—a bob will have to do. It may prove well worth the charge—I understand that a dunking in the Sinister Stream bestows invulnerability. A quality I may find myself in need of before the evening’s out.”

“Oh, you require invulnerability, do you? That’s extra. Messy business, dunking. And someone has to hold you up by the heel. You’d be looking at me a long time before you thought of Achilles’s mother. Now, what was her name?”

“Thetis. I’ve always called her Thetis,” the tramp returned the easy shot. His smile said that he’d understood the survival game was already under way, and the score was deuce on the warm-up alone.

“We’ll cross here,” Digby announced. “Follow me, and mind you don’t get your feet wet.” He leapt with the playful agility of a Greek shepherd boy across the frothing stream that bordered Trumpington Street.

Dickie gave a gracious nod of the head and murmured quietly, “And I’ll be keeping my powder dry, too, young Hermes!”