"There isn't, really. I just feel I'd like to, that's all," said Fatty. "You know, if you're as good an actor as I am, there are certain parts or characters that appeal to you much more than others. I loved being that old Balloon-woman—and I shall love to be that old man. I can act him exactly right."

He gave a realistic sniff and wiped his nose with the back of his hand. The others laughed, and did not tease him over his boasting of being such a good actor.

"You're disgusting!" said Daisy. "Don't for goodness sake start doing that sort of thing in front of your parents! They'll have a fit!"

Fatty got up and hobbled out into the garden, shuffling like the old man. He bent his back and dropped his head. He really was an extremely good actor.

Then he gave another frightful sniff and wiped his nose on his sleeve.

A horrified voice spoke to him. "Frederick! Haven't you a handkerchief? What disgusting behaviour!"

And there was Pip's mother, come to fetch them in to a meal, as they all seemed completely deaf to the gong. Poor Fatty! He went red to the ears, and produced an enormous handkerchief at once. How the others laughed!

With, the help of the others, Fatty managed to get together some old clothes very like the old man on the bench had worn. Pip produced a very old gardening hat belonging to his father. Larry found an old coat hanging in the garage.

"It's been there for years, as far as I remember," he said. "Nobody ever wears it. You might as well have it. It's got mildew inside the pockets, so be careful how you put your hands in them!"

It was easy to get an old shirt and muffler. Fatty produced a torn shirt of his own, and found a muffler down in the garden shed, which he must have left there months before.

He dragged the shirt in the dirt, and it was soon as filthy as the old man's. He dirtied the muffler a little more too.

"What about the shoes?" he said. "We want frightfully old ones. That old man's were all cracked open at the toe."

The shoes were a real problem. Nobody’s father had shoes as old as that. The children wondered if they could buy a pair from some tramp, but when they went out to find a tramp, the only one they met had perfectly good shoes on.

Then Daisy had a brain-wave. "Let's look in all the ditches we pass!" she said. "There are always old boots and shoes in ditches, I don't know why. We might find some there."

Sure enough they did! Larry came across a dirty,-damp old pair, open at the toes and well worn at the heels. He tossed them to Fatty.

"Well, if you think you really do want to wear such horrible things, there you are! But you'll have to dry them or you'll get awfully damp feet, and have a streaming cold."

"He'll be able to sniffle properly then," said Bets. She too had been practising the old man's sniff, much to her mother's annoyance.

"Ill put them under the tank in the hot cupboard," said Fatty. "They'll soon dry there. They'll about fit me. I don't at all like wearing them, but, after all, if it's important to solve the Mystery, it's important to put up with little things like this!"

The trousers seemed quite impossible to get. Nobody's father wore the kind of coarse corduroy that the old man wore. Could they possibly buy a pair in the village shop and make them torn and dirty for Fatty to wear?

"Better not buy them in Peterswood, in case the news gets round," said Fatty. "I wouldn't want old Goon to know I'd bought workman's corduroys—he'd be sure to snoop round and find out why. He's got more brains lately, somehow."

"We'll walk across the fields to Sheepridge," said Daisy. "We might buy a pair there."

Half-way across the fields Pip gave a shout that made every one jump. He pointed to an old scarecrow standing forgotten in a field. It wore a hat without a brim, a ragged coat—and a pair of dreadful old corduroy trousers!

"Just what we want!" said Fatty joyfully, and ran to the scarecrow. "We'll give them back to him when we've finished with them. Golly, aren't they holey? I hope they'll hang together on me."

"I'd better give them a wash for you," said Daisy. "They really are awful. If you wear your pair of brown flannel shorts under them, Fatty, the holes won't show up so much. There are really too many to mend."

Joyfully the Find-Outers went back to Larry's. Daisy washed the trousers, but not much dirt came out of them because the rain had washed them many a time. Bets couldn't imagine how Fatty could bear to put on such horrid old-clothes.

"Duty calls!" said Fatty, with a grin. "Got to do all kinds of unpleasant things, Bets, when duty calls. And a really good detective doesn't stick at anything."

The next day they held a dress rehearsal and dressed Fatty up in the old clothes. He had already got a ragged, sandy-grey beard, which he had cut more or less to the shape of the old man's. He had shaggy grey eyebrows to put on too, and wisps of straggly grey hair to peep out from under his hat.

He made himself up carefully. He put in some wrinkles with his grease-paints, and then screwed up his mouth so that it looked as if he hadn't many teeth.

"Oh, Fatty—you're marvellous!" cried Bets. "I simply can't bear to look at you, you look so awful. Don't stare at me like that! You give me the creeps! You're an old, old man, not Fatty at all!"

"Wassat?" said Fatty, putting his hand behind his ear. He had very dirty hands indeed—and this time he had remembered to blacken his nails too. He really looked appalling.

"What's the time?" he asked, for he had taken off his wrist-watch, in case it showed. "Oh, twelve o'clock. Well, what about shuffling off for a snooze in the sun, on that bench? My double won't be there, because he said he never goes out till the afternoon. Come on. I'll see if I can play my part all right!”

"We'll all come," said Pip. "But well not sit near you. Well go and have lemonade in that little sweetshop opposite the bench. We can keep an eye on you then, and see what happens."

Fatty, after sending Larry down his garden path to the back gate, to see if the coast was clear, shuffled down, hoping that nobody in his house would spot him. He didn't want his mother to get curious about the odd old men and women that seemed to haunt her back-entrance.

Once out in the road, the other four children kept near to Fatty, but not near enough to make any one suspect they were with him. He shuffled along, dragging his feet, bent and stooping, his hat well down over his ears.

"He's just exactly like that old fellow we saw!" whispered Bets to Daisy. "I'd never know the difference, would you?"

Fatty did a loud sniff and the others grinned. He came to the sunny bench and cautiously sat himself down, giving a little sigh as he did so. "Aaaah!"

He was certainly a marvellous actor. He sat there in the sun, bending over his stick, the very picture of a poor old man having a rest. The others made their way to the little lemonade shop, and sat down at the table in the window to watch him.

Just as they were finishing their lemonade a man came by on a bicycle, whistling. He was a perfectly ordinary man, in a perfectly ordinary suit and cap, with a very ordinary face. But, when he caught sight of the old man, he braked very suddenly indeed, and looked at him in some astonishment.

He got off his bicycle and wheeled it over to the bench. He leaned it against the seat and sat down by Fatty. The children, watching from the shop opposite, were surprised and rather alarmed. Had this man seen something queer about Fatty's disguise? Had he guessed it was somebody pretending? Would he give Fatty away?

Fatty, too, felt a little alarmed. He had been enjoying himself thoroughly, getting right "under the skin" of the old man, as he put it to himself. He had seen the look of surprise on the man's face. Now here he was sitting beside him. Why?