Awarded after you complete all levels in World 1.
World 1 can be found in the attic of the house and can only be accessed once you have completed the puzzles from the previous 5 worlds.
In World 1 all time flows backwards (using the rewind ability makes time flow normally).
The first couple of levels are fairly simple: just bounce on the enemies to reach the exits.
The final level, however, can be pretty evil. You basically need to run from one side of the screen to the other while you are being chased by a wall of fire.
It may take several attempts to get through it (one section in particular cannot be done unless you get there very quickly) so be patient :)
Once you reach the end of the level, when it appears you have no where to go, simply rewind all the way back to the beginning to reach the true exit.
Work through the Epilogue levels (simply read the books) and you will be awarded with the achievement.
Video was uploaded by MorrowJ (it's a full walkthrough of World 1).