The Gray Angel

Jason Anderson is dead. Long Live Jason Anderson.
Jason Anderson and Phoebe Reyes have been in hiding for two months since the destruction of the Einstein-Rosen bridge, trying to avoid capture by government agents. Phoebe is the prime suspect in what appears to have been a terrorist bombing that destroyed Jason's laboratory. Jason is believed to have died in the explosion, and Wiley Grant is under arrest, held incommunicado in a secret domestic prison.
When desperation finally drives Jason to contact Dr. Tinsworth, and Phoebe to call her brother Al, the couple are forced to abandon their hiding place - and are soon caught up in a conflict between two clandestine non-governmental agencies.
Captured by agents from one of these organizations, Jason agrees to assist them in a research project that has encountered a major problem. Within hours, Jason and Phoebe find themselves travelling back into a bleak and frightening future, hoping to find the key that will change the course of history, enabling the planet to avoid the fate of the Seafloods...