SOLVED. Horror book about mental patients using ley lines [s]

[Jinx]

This book is about a man (I want to say David? Not sure though) he is looking at a manor to buy with a tennis court, there is a spate of murders with old, missing mental patients, using ley lines to travel underground to find their victims, they drag their victims through walls unless they are wearing crosses which stops their victims being dragged into the darkness fully. There is an ex of the main character.....Karen, leggy and described as a bit of a bimbo who try's to talk the man out of the madness he is spouting. It's a very dark book as I recall but for the life of me I cannot recall the name of the book or the author who wrote it so would be really thankful for any help
Cheers

[Lobstergirl, au gratin]

Walkers?

There is a mental hospital, a character named Karen, and it sounds like the protagonist is Jack.

[Jinx]

Lobster girl I LOVE you!!! That's it! !!! I've been looking for that book since I lost it five years ago but could not recall the name!!! Thank you! !!!

[Lobstergirl, au gratin]

You're welcome. I didn't search very hard - your reference to ley lines rang a bell of another thread I remembered.

https://www.goodreads.com/topic/show/...

[Jinx]

I've been searching for this book for ages I can recall the plot but that was it really lol I've just gone to my second hand book dealer (great guy) and he had it!!! Plus two more by the same author. Happy lady here so thank you once again :)