They'd sent him in because intelligence said the Nazis were building a superweapon. This wasn't technology. The Nazis were summoning demons. Joe knew he didn't know anything about magic, and he'd never heard of a Sunday School that went into the specifics of demon summoning.

His hadn't for sure.

And anyway, he needed to know more about exorcism than summoning now, assuming you could exorcise something that had already been caught.

It started talking again. "You can look at me now."

Joe turned his head slowly, following the corner of the helmet's eyeholes. By the time he reached the creature, it had changed.

A man stood in the middle of the circle. With the brush cut, blond hair, and bulging muscles, he looked like a stereotype.

"Call me Gunther. It's as good a name as any, and while you're at it, step on the circle."

Joe thought about it. "Aren't I supposed to ask for three wishes first?"

It laughed. "I don't do wishes.  I do contracts. Think of it as one wish with multiple points if you want. And make it quick. Meeting the man who summoned me will be a lot more fun if I'm outside the circle."

From outside and below came the noise of men shouting in German and English and the sounds of automatic weapons firing.

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Joe said, "OK. First, you don't attempt to hurt me or my family, or any of my descendants."

"I wouldn't anyway. You're helping me out, right? But think about it, given enough time everyone will be descended from you, and I'm an immortal mercenary. See how that might cause problems? How about we cap it at three generations? You won't even know them after that."

Joe was nineteen years old. He'd broken up with his last girlfriend before the war even started. With a shrug, he said, "Sure."

He thought about it some more. "Immortal mercenary? So could I send you on a mission? Could I have you kill Tojo, Hitler, and Mussolini?"

"Yeah, but that would be it. Nothing else, and then I'd be done. No protecting future generations. I'd take a list of my targets and go."

And then whatever he was, Joe thought, he'd be free to do anything he wanted.

"Uh... Skip that then. How about you work on my side for the rest of the war, and if anything else comes up after that, you stay on my side."

"That works for me. I'm not particular about sides."

The voices below them in the house began to grow louder. The sound of feet thudded against stairs.

"If you've got anything else," Gunther said, "you'd better hurry."

With the threat of immediate combat, Joe could only think about getting into position to fight whatever and whoever would be coming through the door.

"Tell you what, it seems like you're having a hard time with this. I'll make it easier. I'm good at two things, killing people, and making music. I'll teach you, or whoever you want how to fight better, or play music or both."

"You're offering me piano lessons?"

"Piano, guitar, Hawaiian nose flute, whatever. And don't forget the fighting."

They were nearly to the door.

Joe pointed both arms at the door, fingers ready to tap his palms and start firing. Nodding, he said, "I'll take it. I agree."

"Then we're in agreement. Break the circle."

The door to the room shattered, and pieces landed on the floor, none of them crossing the circle.

The man ducking his head to step inside couldn't be a normal human being.