At this point, when everything was going as sweet as a nut and I was feeling on top of my form, Mrs Pringle suddenly socked me on the base of the skull with a sandbag. Not actually, I don't mean. No, no. I speak figuratively, as it were.

'Roderick is very late,' she said.

You may think it strange that the sound of that name should have sloshed into my nerve centres like a half-brick. But, take it from me, to a man who has had any dealings with Sir Roderick Glossop there is only one Roderick in the world—and that is one too many.

'Roderick?' I gurgled.

'My brother-in-law, Sir Roderick Glossop, comes to Cambridge tonight,' said the prof. 'He lectures at St Luke's tomorrow. He is coming here to dinner.'

And while I stood there, feeling like the hero when he discovers that he is trapped in the den of the Secret Nine, the door opened.

'Sir Roderick Glossop,' announced the maid or some such person, and in he came.

One of the things that get this old crumb so generally disliked among the better element of the community is the fact that he has a head like the dome of St Paul's and eyebrows that want bobbing or shingling to reduce them to anything like reasonable size. It is a nasty experience to see this bald and bushy bloke advancing on you when you haven't prepared the strategic railways in your rear.

As he came into the room I backed behind a sofa and commended my soul to God. I didn't need to have my hand read to know that trouble was coming to me through a dark man.

He didn't spot me at first. He shook hands with the prof and wife, kissed Heloise and waggled his head at the Exhibits.