Children's fiction these days is so all-knowing, so cynical, even, that possibly only a first-time writer can bring back to it the naivete that it has all but lost. Perhaps Val Tyler, author of "The Time Wreccas" has not noticed how popular the wickedness of Artemis Fowl is, or the glibness of Hermione Grange (from the Harry Potter series), or maybe she has opted not to take a cue from them. If avoiding the vogue for cynicism is a conscious decision, it's pretty brave of her.
Tyler's heroes, Tid and Sofi, are absolutely bad -- at being bad. Tid is a Guardian, grandson to Old Father Tim. Unknown to the human world, his people secretly look after the most precious thing of all, Time. He looks up to his grandfather, who is just putting the finishing touches on a magical timepiece that took 100 years to make, but will keep time for 1,000 years more.
Sofi is a Wrecca. Her people dwell in the Underneath and know her only as Snot. (It isn't such a bad name, when you consider that her brethren have names like Snivel and Stupid.) They are all as bad as their names, except for Snot, of course, who just cannot bring herself to be as quarrelsome, dim-witted and wicked as Wreccas are supposed to be.