The Kraken Wakes by John Wyndham

A newly married couple, both radio journalists, are taking their honeymoon on a cruise liner.  One evening they see five red meteors crash into the sea.  It is the start of an alien invasion of the Earth in which the invaders colonize the deep sea trenches and then start to move upwards onto the land.  An exciting, apocalyptic tale set in a post-war world in which governments are stupid and short-sighted.  Contains one or two quite contemporary themes, but is dated in parts.  The aliens remain unseen and inexplicable throughout which makes them really threatening.  A good bed-time read, and well worth the £1.49 I paid for it at the local Oxfam bookshop.

Update on Sat 2005-07-16 by Tristram Brelstaff

It so happens that BBC Radio 7 are in the middle of broadcasting a reading of this book in 16 half-hour episodes.