“But look here! Why don’t we stop faffing about and ask the chap Fanshawe a few direct questions? If he’s at home, that is. He seems to be keeping his head below the parapet. I had a call from the senate house just before you arrived. He was supposed to be at a ceremony on their lawn this afternoon, handing out certificates of some kind, but he didn’t turn up. I told them I’d look into it.”

“Always ready for a bit of lion-bearding,” Redfyre said cheerfully. “Coming, Miss Wells?”

The door to the set of rooms on the top floor of Cromwell wing was a formidable obstacle. Of thick wooden planks itself, it bore a further layer of defence drawing—pinned to it. oak up, it said firmly on the back of an envelope. In a Cambridge college, this signified that the traditional medieval oak screen barring entry (long vanished now) was erected. Keep out! it warned. Its authority was never breached.

Dr. Wells and Redfyre automatically backed off on seeing it and looked at each other, puzzled and wrong-footed, neither man wishing to break with centuries-old custom.

Rosa was unimpressed. “Such nonsense!” she said and tore the notice down. “Father, you must do something about this silly tradition. Even the bedders obey it. Look—one of them’s abandoned her bucket and mop still full of soapy water in the alcove over there, rather than carry it all the way downstairs again to the sluice room. Oak-ups are bad for housekeeping! And judging by the smell creeping out from under the door, the poor lady’s going to have her work cut out when she finally gains entrance.”

As one, the two men stepped in front of Rosa and began to mutter suggestions that she should at this point leave matters to them.

Pale faced, she seemed to understand. “No, Pa. No, John,” she said calmly. “Three is a more useful number. You may need a runner. Do what you have to do. I promise I won’t faint or squeal.”

The two men eyed up the solid door and then looked at each other.

“I’m a CID inspector,” Redfyre said firmly. “I can break into any premises I suspect of harbouring a crime without a warrant.”

“And I’m the master of this college,” said Cornelius Wells. “Short of necks, perhaps, I can break anything I like under this roof. Your shoulder or mine? Both together?”

With a tut of irritation, Rosa nipped in front of them. “No keyhole, so no one’s locked it from the outside. I don’t think any of these old rooms have so much as a bolt on the inside. Let’s try this first!” she said and lifted the catch.

The door began to swing sweetly open on oiled hinges.