The Ancient Future - Atlantis Vol 2

The bad guy in these books just doesn't stay dead.  Time travel yarns are confusing at the best of times. I think there are some clever twists here when returning from a time zone ie you have to remember not to arrive IN time but rather to arrive OUT time. This means you will get there just after you left because if you get there before you leave then there is no need to go as you have already done your task and are back from it and then there will be two of you in that time space. Simples.