Mr. Goon jumped violently at the noise. He glared. Buster also jumped. He went to Fatty.

‘Not pleased even now, Mr. Goon!’ said Fatty sweetly. ‘Oh dear - there’s no pleasing you at all, I’m afraid. Wait a minute - I believe I’ve got a really good clue to hand you - ah, here it is!’

He took out a match-box and gave it to the policeman. Mr. Goon opened it suspiciously. It was a trick match-box, and, as Mr. Goon opened it, he released a powerful spring inside which sprang up and shot the match-box high in the air. Mr. Goon got quite a shock.

He went purple, and his eyes bulged.

‘So sorry, so sorry,’ said Fatty hastily. ‘It must have been the wrong match-box. Wait a bit - I’ve got another...’

If Buster had not been there with his ready teeth Mr. Goon might quite well have boxed Fatty’s ears. He looked ready to burst. Fearing that he might say something he ought not to, poor Mr. Goon hurriedly mounted his bicycle and rode up the drive, breathing so heavily that he could be heard all the way to the kitchen-door.

‘He’s gone to talk to Mrs. Moon again,’ said Pip. ‘I expect they’ll come to blows! Let’s get on. Oh, Fatty, I thought I should burst when that trick match-box went up in the air. Goon’s face!’

They strolled down the lane to the river. It was pleasant there, for a breeze blew across the water. The children found a sunny place beside a big bush and lay down lazily. A swan came swimming by, and two moor-hens chugged across the water, their heads bobbing like clockwork.

‘Let’s forget all about the Mystery for a bit,’ said Daisy. ‘It’s so nice here. I keep on thinking and thinking about those letters, and who could be writing them - but the more I think the less I know.’

‘Same here,’ said Pip. ‘So many Suspects - and not one of them could apparently have Done the Deed. A most mysterious mystery.’