Butch Karp/Marlene Ciampi & Family - NY District Attorney Butch Karp & his wife Marlene Ciampi have been around a long time in Robert K. Tannenbaums novels. Marlene has gone from a prosecutor to millionaire owner of a private security firm & back again to an investgator & attorney. She always seems to get caught up in trouble (and usually winds up killing someone) while husband Butch tries to cope with being married to someone who skirts the law. Never a dull moment in these novels.
Alex Cross - James Patterson's Alex Cross Novels are always good and have also featured great villains that will turn up in a couple of novels down the line if they happen to survive their first appearance.
Lucas Davenport - Another cop series in John Sandfords Prey novels. Always interesting to see what Davenport will do next.
Odd Thomas - Although Dean Koontz's character has only starred in 2 novels, he is a very memorable character nonetheless. He has the strange ability to be able to see the spirits of the dead (including Elvis
