In the present day, a group of people wash up on a beach on the Western coast of the USA. But these are not merely people who have been involved in an accident at sea, but really people from the future who are seeking refuge in a prior time, a time when people were more free.
The main element of transhumanism in The Crossing comes in the form of "Apex" which is some kind of gene therapy, or mutation, that causes those people to have heightened abilities, or be "superhuman" if you will. With one of the main characters possesing super strength, speed and eyesight among other traits.
Time travel is also a major component of the story-line.