I wake up to someone rubbing my back.

‘I see you went to Bao Mansion?’ Por Por says softly as she touches Ting Ting’s talisman necklace lying beside me on the pillow.

I turn over and sit up. ‘Are you angry, Por?’ Then, without waiting for an answer I say, ‘I’m sorry I told Ting Ting your secret. I didn’t mean to. It just came out.’

Por Por is quiet for a moment then says, ‘It’s all right. I am partly to blame, too. At my age I should know that the only way to keep a secret is to keep it to yourself.’ She smiles and pushes my hair off my face. ‘You were very brave to go back there alone.’

‘I had to make up for what I did,’ I say. ‘Is Ting Ting all right?’

‘They are keeping her under observation a while longer. But she’ll be fine. Ting Ting’s a tough little you tiao, doughnut.’

Por Por gets off the bed. ‘I must prepare for tonight.’

‘But you haven’t slept all night,’ I say, worried. ‘Why don’t you wait a few more days, then Ting Ting and I can help you.’

‘No. Shen Da Pai is far too dangerous for you to be involved. And he needs to be dealt with as soon as possible so he won’t become more powerful.’

‘I met him yesterday,’ I say, closing my eyes.

I feel Por Por stiffen.

‘It was just getting dark and I was down in the hidden room, looking in the strongbox for Ting Ting’s necklace.’

‘You found the strongbox?’ Por Por’s says.

‘I saw some strange things in there,’ I say. ‘Bad things that smelt so horrible I wanted to vomit. I couldn’t even touch them, they were so awful.’

‘Hmmm …’ says Por Por, shaking her head. ‘Black talismans. So that’s where Shen Da Pai is drawing his power from. They must have been given to him by a black magician. When your training involves special powers, you are often tempted to use these to help yourself instead of helping others. Someone who uses his powers in this way is called a black magician.’ Por Por nods as if to herself. ‘That strongbox is Shen Da Pai’s strength, but it is also his weakness. If I can get to that box …’ She starts to walk out of the room. ‘I have a lot to do, Little Cloud.’

I hop off the bed and follow her. ‘Take me with you, Por Por,’ I say. ‘Perhaps I can help you. I was able to control Shen Da Pai with my ghost song. That’s how I got away. Please let me go with you tonight.’

Por Por stops at the doorway and turns. She shakes her head. ‘Not this time, Little Cloud. He is far too dangerous. But get dressed and I will show you how a ghost-hunter replenishes her energy.’

We go outside and take the steps that lead down to the canal where the fish pond is.

‘Rocks have enormous energy because they come from the centre of the earth,’ Por Por says, as we stand by a large rock near the pond. She leans her back against the smooth surface of the rock and shuts her eyes. Her arms go limp at her sides. I hardly see her breathing, and the corners of her mouth are smiling, just a little, as if she’s having a beautiful dream. She stays like that for a long time, not moving a muscle. I look out over the canal. The water is the colour of a dense forest. Dark rain clouds have covered the sky and I hear the rumble of distant thunder. When her eyes open at last, they are bright and clear again. ‘There, I feel much better now,’ she says, straightening her jacket. Even her voice sounds younger, like an early morning birdsong.

We go back up into the house. I sit at the kitchen table and watch her getting things ready for tonight. She puts two swords – a coin sword, and one with talisman symbols carved along its steel blade – into her long green bag. Pouches of herbs, jars of silver dust, strips of paper, a set of bells and her mingshen mirror all go into the bag. Then she sits a jar of black ink on the table. Very carefully she begins to paint talisman symbols all over her arms with a small brush. She takes off her shoes and socks, puts her foot up on the bench, rolls up her pants and begins to paint each leg – even the soles of her feet.

‘When fighting a particularly dangerous ghost, these talismans are essential,’ she says, blowing on the last symbol on her big toe to help it dry. She screws the lid back on the ink bottle, washes out the paintbrush in water, and puts it all away in the cupboard.

‘I must go and pray,’ says Por Por, and she closes the door to her room.

I say my own little prayer as a streak of lightning cracks open the sky. ‘Keep her safe, Mama,’ I whisper. ‘Please keep her safe.’

For the first time since I came to China, I wish Ting Ting were here to keep me company, to keep my mind off where Por Por is going and who she is going to meet. I would even let her win a game of weiqi, just this once, to keep Por Por safe.