4 Books Found

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"Romance thriller novel. Seems to be an older book, possibly from the 80s or 90s. The main character is a women’s whose apartment catches fire in a city. A man helps her to find a place to stay in which it is his families secret home (I want to say in the mountains). This man possibly owns a gym? She finds out that he and his family are secret undercover detectives. They help to solve who burned her apartment building down. There is romance between the woman and the man that saved her."