Madsen Pirie has just had two children's stories published. He says that fantasy and science fiction at the children's level is now nearly all fantasy about elves, warlocks, magic swords and supernatural powers. He prefers writers like Heinlein, Asimov and Clarke, who followed the rules of possible science.

Pirie's books are Children of the Night and Dark Visitor. These are children's stories, and quite exciting ones, too. The thing that strikes you is how much action there is. There are no long-winded asides. Stuff just keeps happening. The other thing is that both are very visual – you can't help visualizing. I wonder if he's after the movie rights.

I read Children of the Night first. Interestingly, it looks like fantasy, set in an alternative earth with barons and bishops. However this one has flying machines (the excellent dragonflies) and blue power globes. It is science fiction dressed as fantasy, and it sweeps you along. I liked the rat. Normally a kid with a pet is the superior partner, but not here; the rat is smarter. There's a great climax as the characters ride out the blast of an anti-matter bomb from a sailing ship. The ending hints at a sequel, which I hope happens because I got to like the characters.

I liked Dark Visitor better. It's hard SF and makes particle physics into child's play. There's a terrific build-up of tension as the mysterious dark ship is probed, and the story rattles along as some of its secrets come out. I liked the kid with attitude, the sleeping stranger who's been on a cycle of deep space missions. This book has some great one-liners, and every chapter ends on a line that makes you turn the page. I found the ending very satisfying.

There's a lot here for adults as well as the target audience of 13 year-olds. I suppose if he turns out books like this regularly, he might build up a following. Children are serial readers of authors they like, and there's enough in these to attract a following.