The Creeper had already begun to move about the tow-path and condense on a green hedge near the lockhouse. It was threading gently into the trees and making wraiths of those that could be seen. The night smelt dank. Small sounds were exaggerated and everything was damp to the touch.

‘Damn,’ Alleyn whispered. ‘We don’t want this. Where’s that chap—oh, there you are.’

The considerable bulk of Tillottson’s PC on duty, loomed out of a drift of mist.

‘Sir,’ said the shape.

‘You know what you’ve got to do, don’t you? Nobody to leave the Zodiac.’

‘Yes, sir.’

‘Where’s your nearest support?’

‘T’other bank, sir.’

‘And then?’

‘This side, up beyond Wapentake Pot at th’ crossroads. T’other side, sir, above pub at main road crossing.’

‘Yes. Well, you’d better keep well down by the craft, with this mist rising. The Skipper’s putting her in the lock before long. If there’s an attempt you should be able to spot it. If anyone tries to come ashore, order them back and if they try to bolt, get them.’

‘Sir.’

‘Watch it, now.’

‘Sir.’

‘A dull-sounding chap,’ Alleyn muttered.

They climbed up to the road and crossed the main bridge below the lock to the left bank. The formless voice of the weir obliterated other sounds. Blown flecks of detergent mingled with the rising mist.

‘We’ll have a bloody tiresome drive back to Toll’ark, if this is the form. Where’s that car? And where—oh—here you are.’

Thompson and Bailey loomed up. They’d completed their job along the riverside and were told to come back to Tollardwark. The London police car gave a discreet hoot and turned on its fog lamps. They piled into it. Alleyn called up Tollardwark on the sound system and spoke to Tillottson.

‘They won’t talk,’ Tillottson said. ‘Not a peep out of them.’

‘We’re on our way. I hope. Over and out.’

The local man gave them a lead on his motorbike. When they reached the crest of the hill they found the mist had not risen to that level. The man at the crossroads flashed his torch, they turned into the main road and in eight minutes arrived once again at Tollardwark.

In the office where Troy had first encountered Mr Tillottson, he sat behind his desk with a telephone receiver at his ear and a note pad under his hand. He repeated everything that was said to him, partly, it seemed for accuracy’s sake and partly for Alleyn’s information.

‘Ta,’ he said and signalled to Alleyn, ‘Yes, ta. Mind repeating that? Description tallies with that of “Dinky Dickson”, con man 1964. Sus. drug contact Kings Cross, Sydney. Place of origin unknown but claims to be Australian. Believed to be—Here! What’s that? Oh! Oh, I get you! Unfrocked clergyman. Australian police got nothing on him since May ‘67 when heavy sus. drug racket but no hard proof. Very plausible type. Ta. And the US lot? Two hundred and seven left-ear-deficients on FB records. No Hewsons. Might be Deafy Ed Moran, big-time fix, heroin, Chicago, undercover picture-dealing. Expatriated Briton but speaks with strong US accent. Sister works with him; homely, middle-aged, usually known as Sis. No convictions since 1960 but heavy sus., Foljambe—here, wait a sec. This is important—heavy sus., Foljambe—accomplice. Message ends. Ta. What about Pollock, then? Anything come through? Pardon?’