All Jules wanted to do was ask Gen out. He had battled his brain (literally) for who-knows-how-long about how to go about it and whether to even do it.
And just when he's finally about to pop the question, some kid with technicolor hair and a talking Coat materializes in Gen's room. Not a situation conducive to asking a pretty girl out on a date.
As it turns out, Theo is from waay in the future, which explains the whacky hair and ad-spewing Coat. In his time, he won a contest to be the first kid to use the newest JumpMan - the device that allows everyone to go back in time. But there's something wrong with this new (new?) JumpMan - and that's why Theo's in Jules's time. That's also why he can't get back to the future.
Well, what are Jules and Gen supposed to do? Let Theo try to make it back to the future without helping? Of course not.
Already, it's not such an original plot. (Unless there's a dearth of time travel novels in Australia, which is where the author is from - something very helpful in decoding the book's lingo.) The writing is decent, and there are some seriously funny parts - particularly Jules's squabbles with his own brain.
Jules, in fact, is pretty much the only likable person around. He's the classic not-too-popular, not-too-handsome kind of stock character that you really can't help loving because no one else does. Gen is also a stock character - the pretty, popular, girly-magazine-reading girl with (theme music) girl powah. Why Jules is so in love with her, I haven't a clue, because he really is smarter than that.
I'm pretty sure we're supposed to like Theo, the off-the-wall, funny, careless guy from the future who has crazy hair and an awesome Coat. But I didn't. Why exactly did he hate Jules's guts right from the start? Why does he think Gen is awesome but not Jules? Why is Gen so enthralled with Theo? (Oh, right - because he's funny and looks cool. That's it.) He just came off as some pompous jerk, bragging about how much better the future is than the 21st century. (And yet there's no sarcasm or scorn for the Neanderthals they go back in time to see... how does this work, exactly?)
For a long time, zombies have been a dramatic symbol of modern social structure and politics (or so they say). Werewolves and vampires are dramatic symbols of human failings and morality. Time travel, I think, has become the dramatic symbol for eco-friendly, go-green messages. I find nothing inherently wrong in this... except that Don't Touch Anything handles its own message less than gracefully.
It's basically 'You bad, 21st century humans you, destroying the earth. Be ashamed.' There's one part where Theo is explaining how the world was used up (an inevitable plot twist). In essence, he tells Jules and Gen, 'Your time was the biggest mistake in the world.' Jules and Gen apologize - literally. 'We're sorry.' Is it just me, or is this not really fair? And don't get me started on the whales - no way do I want whales to go extinct, but can Valentine not come up with a more original way of expressing the horrors of extinction?
I mentioned Neanderthals a little before now. I found it interesting that Valentine never goes back in time to any documented period of history. Jousts and beheadings are mentioned, but the only trips that Jules, Gen, and Theo take (besides a very quick materialization in ancient Egypt) are to the times before mankind (supposedly). It's all oooh-pre-Big-Bang! and look-the-first-animal. I don't believe evolution, so maybe it's just me, but it made the book seem more like a textbook than an interesting story.
In retrospect, I realize that I made Don't Touch Anything sound like a horrible book. It's not. It was interesting, even thought-provoking a time or two (though I'm not sure any halfway-decent time travel book isn't). But I think Valentine could have done better, put a little more effort and a little less textbook material into it. As it was, it barely felt like he tried. For more interesting, well-pulled-off time travel, I'd suggest Linda Buckley-Archer's Gideon trilogy or The Dreamhouse Kings series by Robert Liparulo.