‘Andrea?’ says Billie to Jack, when they have rounded the corner.

Jack grins a little sheepishly and shrugs. ‘I talked to Mum yesterday. I know you said we weren’t to talk to anyone about the Secret Mystery Club, but you scared us so much.’

‘But why didn’t you tell me she was friends with your mum on the way here?’ Billie says crossly. ‘I was scared, Jack! Really scared!’

Jack bends down to scratch Scraps behind his ears. Then he looks up and gives her a strange look. ‘It’s not a nice feeling, is it?’ he says seriously. ‘When a friend tries to scare you on purpose.’

Billie feels her cheeks get hot. She looks down at the ground.

Jack is right, she thinks. It was mean of me to scare him. And Mika and Alex. It serves me right that Jack wanted to scare me back.

‘Sorry,’ she says, quietly. ‘I wanted to have a mystery to solve so much. And I thought it was just a bit of fun. But I guess I got carried away.’

Jack smiles and passes Billie the basket. ‘That’s OK. Come on, we’d better get back. We don’t want to scare our parents now, do we?’

Billie laughs. She walks alongside Jack swinging the empty basket.

She feels buzzy with relief.

‘But come on,’ she says, shaking her head. ‘You have to admit, it really does look like a witch’s house! And, well, she does kind of dress like a witch.’

‘I know!’ says Jack. ‘You should have seen how messy her house was inside. I guess she’s too busy making her sculptures to clean up. Mum says she’s a famous artist. Her sculptures were pretty cool.

You should come see them with me one day.’

‘Maybe,’ says Billie. She thinks about the strange white shapes she saw when she was peeking through the side window, and tries to imagine what weird sculptures might be hidden under there. ‘She still spooks me a little though.’

Jack laughs. ‘You? But you’re the bravest person I know, Billie! You’re not scared of anyone!’

Billie grins. Then she puts on a spooky old witch voice. ‘Obviously not as brave as you, my friend!’

Scraps barks and the two of them jog along the street. They arrive at Billie’s house and Jack waits for her to go inside.

Just then, Billie sees something white on the doorstep. ‘Jack! Come here!’ she calls.

Jack bounds up to Billie with Scraps close behind. ‘What is it?’ he says.

Billie bends down to pick up the thing at her feet. It is an envelope, made from stiff white paper. They peer down at the curly black writing on the front and read:

Billie gasps. She tears open the envelope and tips out a large piece of folded white paper.

‘What does it say?’ Jack asks, trying to peer over her shoulder.

‘I don’t know,’ Billie says slowly. She turns the paper around and around. ‘I think it’s in code.’

He and Billie stare at the paper. It has strange black squiggles running across it.

‘Wow,’ says Jack.

‘I’ll bring it to school on Monday,’ Billie says excitedly. ‘It looks like the Secret Mystery Club has our first real mystery to uncover!’