‘So, it’s a fight you want, do you?’ Inspector Cheddar was daydreaming. In the dream he was an expert at karate. He’d just caught the burglar, who was dressed in a Santa Claus suit with a sack marked BOOTY, sneaking down a chimney. HI-YA! KER-CHUNG! SMACK-POW! With a few clever kicks and chops the burglar was at his mercy. Inspector Cheddar whipped out the handcuffs. ‘You’re under arrest, mate,’ he whispered. Then he stared in disbelief. The burglar had grown wings. In a flash he’d turned into a black-and-white bird and flown back up the chimney and away, cackling loudly to himself. ‘Chaka-chaka-chaka-chaka …’

‘What are you babbling about now, Cheddar?’ The Chief Inspector of Bigsworth roared.

Inspector Cheddar woke with a start. He was in the police station at Bigsworth puzzling over paperwork, not catching burglars at all! ‘Sorry, sir!’

‘You should be!’ The Chief Inspector shouted. ‘Your wife’s on the phone. You need to get over to the school. The headmaster wants to see you. NOW!’

Mrs Cheddar was waiting for him in the headmaster’s office. So were Callie and Michael.

‘Dad!’ Michael cried as soon as he saw him. ‘We know where the stolen jewellery is!’

‘It’s under the pier, Dad!’ Callie said excitedly. ‘In the magpies’ nest. We saw it!’

‘Huh-hum.’ The headmaster interrupted sternly.

Inspector Cheddar sat down opposite the headmaster. He looked at Callie and Michael, puzzled. Callie’s face was flushed. Michael had seaweed in his hair. Little piles of sand leaked out of their trainers on to the headmaster’s floor. Inspector Cheddar couldn’t understand it. They were clearly in trouble but they both looked as if it were Christmas.

‘I’m afraid your children ruined the entire school outing,’ the headmaster sighed. He was a kind man and he didn’t like telling people off, but spoiling the school trip was going too far, even for him. ‘It seems they decided to go off by themselves to do a bit of detective work when they were supposed to be on the dodgems.’

‘But, Dad!’ Michael protested. ‘Mrs Tucker was right. The magpies are involved in the burglaries!

‘Huh-hum!’ The headmaster interrupted again. ‘Luckily, the alarm was raised before they got too far. Mrs Cooper, the Year 3 assistant, spotted them in Sea Shell Drive.’

‘We saw Atticus!’ Michael told him proudly. ‘We followed him to the pier.’

‘He was having a row with the magpies,’ Callie gabbled. ‘He’d taken off his handkerchief.’

‘Without the handkerchief he answers the description the Pearsons gave of the cat they saw at the window!’ Michael explained. ‘He’s been working with the magpies. He’s been taking the jewels.’

‘But don’t worry, Dad,’ Callie said quickly. ‘He’s not going to do it any more.’

‘Obviously this is quite a serious matter,’ the headmaster began again.

‘He’s changed his mind about being a burglar!’ Callie rattled on. ‘He’s started to give things back!’

‘We followed him to Sea Shell Drive,’ Michael said. ‘He returned the lady’s emerald necklace!’

Callie swung her legs to and fro. ‘We saw him, Dad!’

‘Normally I’d involve the police when a child goes missing …’ the headmaster said to Inspector Cheddar.

‘Can’t you see?!’ Michael shouted. ‘He’s trying to say he’s sorry!’

‘But as you are the police,’ the headmaster gave up. He had never known such rude children. ‘I think on this occasion I’ll just let you handle it.’

As soon as they got into the car, Michael and Callie started talking at once.

Inspector Cheddar held up his hand for silence. ‘I don’t want to hear another word about it!’ he said in a dreadful voice. He turned the key in the ignition.

‘But, Dad …’

‘I said, ZIP IT!’ he shouted. This was an expression Inspector Cheddar usually reserved for people who complained about parking tickets. Now he was using it on his own kids!

Callie started to cry.

Michael bit his lip. ‘We were just trying to help,’ he said quietly.

Mrs Cheddar glared at her husband. She put an arm round Callie.

Michael held her other hand.

‘They might be telling the truth, you know!’ she hissed. ‘Have you thought about that? Maybe they’re right. Maybe Atticus was the burglar, but now he’s changed his mind. Maybe he was trying to say sorry. Maybe the magpies are involved. They tried to steal your badge, didn’t they?’

Inspector Cheddar gripped the wheel. Magpies! Nests full of stolen jewellery! He’d never heard anything so ridiculous in his life. Everyone had gone mad since Atticus Grammaticus Cattypuss Claw arrived. He needed a cup of tea!

A few minutes later they pulled up outside number 2 Blossom Crescent. Mrs Cheddar let them out in silence and drove off back to Toffly Hall for the final preparations for the fair. Inspector Cheddar marched up the path and let himself in. He threw open the kitchen door and went to fill the kettle.

‘WHOAOAOAO!’ He tripped over the cat basket and banged his head on a cupboard. Inspector Cheddar swore. Atticus again! What was the cat basket doing there anyway? It was normally tucked away beside the fridge. He nudged it with his foot.

CLINK! Something clattered on to the tiled floor from beneath the spongy mattress. Inspector Cheddar stared. His wife’s best brooch! What was that doing in the kitchen? She normally kept it upstairs in a jewellery case in their bedroom.

Inspector Cheddar bent down to pick it up. He examined the mattress. It was all lumpy and bumpy. Something else was hidden underneath. He picked it up gingerly. A tangled heap of jewellery tumbled out. His mouth fell open.

‘Atticus!’ he whispered. His face went green. ‘So the children were right. It was you all along!’

Michael and Callie stood in the doorway aghast.

‘No!’ Callie cried. ‘It’s not Atticus’s fault! We told you! He was stealing for the magpies! But he doesn’t want to any more. He’s taking things back!’

‘He’s changed his mind, Dad,’ Michael yelled. ‘I promise you, he didn’t steal Mum’s brooch!’

Just then Atticus’s head appeared through the cat flap, followed by one paw, then another. He looked down. Something was wrong. There were feathers on the floor.

‘Run, Atticus!’ Michael shouted. ‘Run!’

Atticus stared at the cat basket. The jewels blinked back at him. The magpies! They had framed him!

‘Quick, Atticus, run!’ Callie yelled frantically. ‘Dad thinks it was you!’

Inspector Cheddar loomed towards him, hands outstretched.

Atticus gulped. Inspector Cheddar’s face had gone from green to red, like a traffic light. ‘Gotcha!’ he hissed. ‘You … you … CAT CRIMINAL!’

Terrified, Atticus tried to wriggle his way backwards out of the cat flap. But backing out of a cat flap is like reversing a car. It’s much harder than going forwards. And he wasn’t as skinny as he used to be. Mrs Tucker was right. He’d been eating too many sardines. He pulled in his tummy and wriggled again. It was no use! He was stuck!

Inspector Cheddar lunged at Atticus and grabbed him firmly under his armpits. He dragged Atticus into the kitchen, picked him up roughly and held him tightly under one arm.

The children watched in horror.

‘AFTER ALL WE’VE DONE FOR YOU, YOU MISERABLE MOGGY!’ Inspector Cheddar shouted. ‘THAT IS WHAT YOU DO TO REPAY US!’ He whipped a set of handcuffs out of his pocket with his free hand. He clicked one end round Atticus’s neck and the other round his wrist. SNAP! ‘You’re under arrest, Atticus Claw,’ Inspector Cheddar said.

Atticus’s ears drooped.

‘CHAKA-CHAKA-CHAKA-CHAKA!’ From some where outside came a harsh chattering cry.

‘The magpies.’ Callie started to tremble. She clung on to her brother.

‘They’re laughing at Atticus.’ Michael shivered.