Jacob was now wearing an old-fashioned bottle green engine driver’s uniform, complete with peaked cap, with the front of his silver-buttoned jacket hanging open to reveal a T-shirt bearing the legend Engineers Get You There Quicker. He looked very sharp and focused, with hardly any blue-gray trails of ectoplasm following him when he moved. Jay was back in the full finery of his original period and looked almost as excited as his future ghostly self, but there was something in his eyes . . . I folded my arms across my chest and gave them both my best hard stare.

“Nice trick,” I said coldly. “I’ll bear it in mind for if we ever need to give someone a coronary. I didn’t know you could do that, Jacob.”

“You’d be surprised at what you can do when you’re dead, boy,” Jacob said cheerfully. “It’s really very liberating.”

Jay looked severely at his future self. “I’m boasting again and I do wish I wouldn’t. We have a plan to save the day, Eddie.”

“Of course,” I said. “Doesn’t everyone? Does your plan by any chance involve blowing up the whole damned universe?”

“Well, no,” said Jay. “Not as such.”

“I like it already,” I said.

“Oh, you tell him, Jacob,” said Jay. “You know you’re dying to, and you’ll only butt in and interrupt if I try. I apparently become very grumpy after my death.”

“Try hanging around this family for centuries,” Jacob growled. “They could make a pope swear and throw things. Listen, Eddie, we have a way to stop the Invaders in their tracks. We’re going to use the Time Train.”

“You’ve only just started describing your plan, and already I hate it,” I said. “Going back in time to undo present events never works. Never never never. It always ends up causing more problems than it solves.”

“Do calm down, Eddie,” said Jay. “Your face has gone a very funny colour, and it really can’t be good for you.”

“We are not going back in time to stop the Invaders before they start their plans against us,” Jacob said patiently. “I know enough about time travel to know that wouldn’t work. I watch television. No, we’ve got a much better idea. We’re going to use the Time Train to sneak up on the Invaders’ home dimension, and attack them from the one direction they won’t be expecting: the past!”

“Run that by me again,” I said. “I think I fell off at the corner.”

“It’s really very simple,” said Jay.

“No it isn’t,” I said. “No explanation that begins that way ever is.”

“Look,” said Jacob, prodding me firmly in the chest with a surprisingly solid finger. “The Invaders come from a higher dimension than ours, right? That means to them, time is just another direction to move in. We can use the Time Train to access their dimension and attack their homeworld from the past! They’ll never see us coming!”