Fatal Mistake by Marie Force - $0.99. It's part of the Monthly Kindle Big Deal sale so it will probably stay at this price during March. Of course, I bought it when it first came out at $3.82.
This is Book #6 in Marie's Fatal series. I absolutely love this series. It's a great blend of romance and romantic suspense that gets better with every book. The set-up is somewhat similar to JD Robb's In Death series (without the futuristic elements), but there are plenty of differences, as well as very different writing styles. I read and enjoy both series, but they aren't actually that similar once you get past the fact that both feature a female police lieutenant, a yummy male lead, and a great group of supporting characters (It's a formula, but it works every time when it's well-executed
).