I think I was halfway through this one when I realized I'd read another book in the series a week or so ago.
So our h got worked over by a con artist. She had an inheritance, and some insurance money, and he used his good looks and charmed her into marriage. Then his partner stole her money, and he "disappeared"...after getting her knocked up.
His identical twin comes behind to a) figure out what happened and b) clean up his mess if necessary. Poses as him for a bit, before finally revealing himself to her. The accomplice is after him for the money. He figures, based on twin's past history, the trail leads to Vegas so they go, and find the end of the trail for twin.
Go back, and with help of local sheriff, and h's retired bounty hunter - brother, set up a trap...that accomplice fails to spring. Instead accomplice walks in an unlocked door and takes them by surprise after everyone has presumably gone home. Fortunately, the bounty hunter was suspicious so didn't.
It was a quick read. I couldn't help but wonder if pregnancy hormones didn't help things along. Also thought H maybe a bit too quick to roll over for a PI. Really hard to imagine him being v. effective as beta as he seemed at times.