The Infinite (Leap Cycle, 1)

We fight crime across time. Leaplings, children born on the 29th of February, are very rare. Rarer still are Leaplings with The Gift - the ability to leap through time. 

Elle Bíbi-Imbelé Ifíè has The Gift, but she's never used it. Until now. On her 12th birthday, Elle and her best friend, Big Ben, travel to the Time Squad Centre in 2048. 

Elle has received a mysterious warning from the future. Other Leaplings are disappearing in time - and not everyone at the centre can be trusted. Soon Elle's adventure becomes more than a race through time. It's a race against time. She must fight to save the world as she knows it - before it ceases to exist.