The Future Is Waiting - Pierre Christin

After the events of The Time Opener, Valerian and Laureline reverted to childhood, and are now living with Mr Albert on 21st century Earth. But in a universe where time travel is a reality, words like ''after'' or even ''now'' can be somewhat... hazy, and elsewhere, in other times, our young but nonetheless adult agents are still working tirelessly to maintain a galactic peace threatened as always by greed and the thirst for power.