“Thaaaaank you,” Alex’s grandfather said. He tossed the dazed little robot high and swung his cane as it fell, batting it away with a mighty crack. Zia stumbled to her knees, clutching her head. Her fliers dropped from the air with a great rattle. But within seconds she was groggily standing again. Her metal swarm started weakly rising.

Alex and his grandfather were already in the Citroën.

“What now?” Alex said as he slammed his door.

“Play it by ear on the roads.” The engine roared as they accelerated out of the parking area. “Try to lose them. Then I’ll get you safely on a train or a plane back home.”

“What?”

“I need to get you out of it now. It was worth taking the shot, Alex, but we’ve tried, we’ve failed, and there we are. I can’t risk you getting hurt. Or worse. You’re right, I should never have dragged you into this. We’ll get you home. Leave the robot with me. If I can get through this, I’ll see it’s destroyed.”

“I’m not leav—”

“Then again.” Alex’s grandfather’s brow creased uncertainly. “Maybe I shouldn’t send you back home alone. They had their eye on you. Maybe I should keep you close so I can protect you. That’s partly why I dragged you into all this in the first place, Alex, to try to keep you safe from . . . Sorry, Alex. I’m finding it a little hard to focus. Bit of a fog on the brain.”

“You can forget it, anyway,” Alex cut in. “It’s not happening, Grandad. I’m not leaving you.”

“Alex. No. I—”

“I’m not leaving you. That’s that. I’m sure I can reach the power again, if I can only work out . . . and even if I can’t, I can still help you.”

“Okay,” the old man said after a minute of silent driving. “Good man, Alex. Well. Here’s the immediate plan, then: we need to lose them, but not lose them. We need to get them off our tail, but we need to get on theirs, follow them. Failing that, we need to work out the significance of the paintings.”

Alex thought again about the reds and blues glowing from the picture on his phone by Harry’s graveside. “I had another idea about that,” he said as the car bounced wildly down the crooked road. “I don’t know if it’s stupid. We said that maybe they needed the actual physical paintings, right? So, could it be something in the paint itself?”

“How do you mean?”