Alleyn’s whistling drifted into the silent room. “Hey, Robin, jolly Robin, tell me how thy lady does,” whistled the inspector. In a very short time he was back again, incredibly changed by a dirty chin, a very ill-cut shoddy suit, a cheap-smart overcoat, a cap, a dreadful scarf, and pointed shoes. His hair was combed forward under the cap.

“Oh!” exclaimed Angela, “I can’t bear it—you always look so frightfully well turned out and handsome.”

To Nigel’s amusement Inspector Alleyn turned red in the face, and for the first time in their acquaintance seemed at a loss for an answer.

“Has no one ever told you you are handsome, inspector?” pursued Angela innocently.

“Fox raves over me,” said Alleyn. “What are you standing there for Bathgate, with that silly grin on your face? Have you ordered the taxi? Have you had a drink?”

Nigel had done neither of these things. However, this was soon remedied and in a couple of minutes they were in a taxi, heading for the Embankment.

“We’ll walk the last part of the way,” said Alleyn. “Here are your tickets. We got these three with a good deal of difficulty. The brethren are becoming rather exclusive. Now do be careful. Remember The Times criticised me for employing Bright Young People in the Frantock case. Repeat your lesson.”

They did this, interrupting each other a good deal, but giving the gist of his instructions.

“Right. Now it’s only eleven-twenty. We’re early, but there will be plenty of people there already. With any luck I’ll spot Banks and you may get near her. If not, drift in her direction afterwards. I’ll be near the door. As you come out brush up against me, and if you’ve been shown the Sage, point him out to each other so that I can hear you. See? Good. Here’s where we get out, for fear of seeming proud.”

He stopped the taxi. They were still down by the river. The air felt chilly and dank, but exciting. The river, busy with its night traffic, had an air of being apart and profoundly absorbed. There were the wet black shadows, broken lights, and the dark, hurried flow of the Thames towards the sea. London’s water-world was about its nightly business. The roar of the streets became unimportant and remote down here, within sound of shipping sirens and the cold lap of deep water against stone.

Alleyn hurried them along the Embankment for a short way and then turned off somewhere near Blackfriars Underground Station. They went up a little dark street that resembled a perspective in a woodcut. A single street lamp, haloed in mist, gave accent to shadows as black as printer’s ink. Beyond the lamp a flight of stone steps led dramatically downwards. They followed these steps, came out in a narrow alley, took several more turns and fetched up at last by an iron stairway.