A long, long time ago I heard part of a radio 4 audio book. I ment to look it up at the time and to read or listen to the rest of it, but forgot, and now have no idea what it was called.
The clues are:
It was really gripping, in a 'war of the worlds' type way.
It involved sea monsters.
The main two characters were journalists (male and female).
Most of the UK flooded but they were able to access a boat to get around.
In one part they were staying in a holiday resort abroad in a hotel many floors up. The sea monsters came up out of the deep ocean and tried to reach into their room to pull them out. It didn't succeed. When they went out later there were deep trails going into the sea where the (mechanical?) monsters had sunk again.
In another part, the shipping industry was suffering because all the boats kept being attacked. They realised it was the sound of the motors attracting the monsters so had to use sail boats or pull 'decoy' boats to try and get supplies to the UK.
Any suggestions?