Out Of Time by Shirlee McCoy

Someone plans to disrupt the 175th anniversary celebration of the Battle of the Alamo–and it's Alamo Ranger Susannah Jorgenson's job to stop the culprit. But that means partnering with Levi McDonall, who skipped town years ago with her heart. Levi's now a Texas Ranger, sworn to protect her at any cost, but Susannah knows she'll pay the price if she falls for him again. She has to stay focused on their goals–to eliminate the threat and solve the murder of Levi's captain. But an unknown killer is watching…ready to eliminate them.