Mrs. Moon looked at the children curiously. Fatty got up. He didn’t want to make Mrs. Moon suspicious about anything.
‘Time I went,’ he said. ‘Your lunch will get cold, Pip and Bets, if you don’t go and have it. See you later.’
‘Here’s your notebook, Fatty!’ Bets called after him, as he went downstairs. ‘Your precious notebook with all its Clues and Suspects! Fatty, are you going to write up the case again? You’ve got some more to put down now, haven’t you?’
‘Chuck the book down to me,’ said Fatty. ‘Yes, I’ll write up the case as far as it’s gone. I bet old Goon would like to see my notes!’
He went out of the garden-door with Larry and Daisy. Fatty did not put on his wig or apron again. He stuffed them into his bicycle basket.
‘Good thing I’d taken them off before Mrs. Moon came in,’ he said. ‘She’d have wondered why you were hobnobbing with the butcher-boy!’
‘Fatty, who do you think is the letter-writer?’ said Daisy, who was burning with curiosity. ‘I think it’s Mrs. Moon. I do really.’
‘I do too,’ said Larry. ‘But I don’t see how we are to get any proof.’
‘Yes, it certainly might be Mrs. Moon,’ said Fatty thoughtfully. ‘You remember that Pip told us she wanted her niece to come here? She might have got Gladys out of the way for that. And yet - there are all the other letters too. Whoever wrote them must be a bit mad, I think.’
‘What do we do next?’ asked Larry.