I'd highly recommend the Jane Whitefield series by Thomas Perry. She's basically a female Jack Reacher!
I would also enthusiastically endorse Barry Eisler's John Rain as well as the novels by Brad Thor, Vince Flynn, Robert Crais, Thomas Perry's Butcher Boy series, the Parker series, Travis McGee, and the Quiller novels. All of these are action-charged and full of nail-biting suspense.
Oh I almost forgot the Jet novels by Russell Blake and his assassin series... in fact all of his work is amazing.
I would also enthusiastically endorse Barry Eisler's John Rain as well as the novels by Brad Thor, Vince Flynn, Robert Crais, Thomas Perry's Butcher Boy series, the Parker series, Travis McGee, and the Quiller novels. All of these are action-charged and full of nail-biting suspense.
Oh I almost forgot the Jet novels by Russell Blake and his assassin series... in fact all of his work is amazing.