I love Patrick Lee. Each book in his "Breach" trilogy is excellent. Sam Dryden features in 3 novels, and the first two were great. This was OK.
In a Patrick Lee novel, the premise is usually crazy, but he brings it home through intrigue, cleverness, good writing, and story....And good bad guys. This novel has really weak and dumb bad guys. There is really only one bad guy, and his henchmen make no sense, and are just "red shirts" in the Star Trek sense... there to die.
The scary and dark intrigue that develops, as two adults try to remember the huge event from their childhood (memory wiped for years) turns into a sort of "meh" event, not all that scary.
This is like somebody setting you up to see a homerun, and then they hit a single to right field with no men on base.