Goodness gracious me; this is without any shadow of any doubt the worst book I have ever read.
Parts 1 and 2 - ok, passable, enjoyable
Parts 3 and 4 - written by an 8 year old explaining how time travel works and a little something on genetic modification. The paragraphs where a group of characters are briefed that Ridley has travelled through time read a little like this
Here's Ridley, he's your father, he's travelled through time on a submarine. All clear, any questions? No, great.
Is followed directly up by
Oh - as you can travel through time, could you go back on your completely destroyed submarine and sort out the end of the world? Please.
We've got a range of submariners here who can help restore a nuclear sub and they all know they'll die when you get to time travel and they won't. Just reverse the route and you'll return to a point in time minus four days where you started.
I think Hayes wrote part 1 and 2 and quite literally thought he'd write the most ridiculous things that the publishing house would take to get it finished. So he did.