If you buy as many goofy mystery / sci-fi / suspense books as I do just because you like the cover, you learn to appreciate it when the books also turn out to be well written and entertaining. Fatal Lady by Rae Foley (1964) turns out to be just one of those books.
Rae Foley was the pseudonym of Elinor Denniston (1900-1978), who also published as Dennis Allan and Helen K. Maxwell. Rae Foley was her most prolific author-name, though, and this book is apparently part of a series of romance/mysteries featuring the sometimes-detective Mr. Potter.
In Fatal Lady, we come into the story after much of the action has taken place: Janet Grant is a wealthy socialite, and her playboy brother Cass married a beautiful woman with an unknown background named Eve. The sister, brother, wife, and father all live together in a fancy townhouse that is attached to the home of their neighbors and close friends, the Frederick's. When Mrs. Frederick confronts Janet and Cass with the news that Eve is having an affair with Mr. Frederick, a famous artist, Cass is enraged. He goes out to the art studio at the back of the property and comes back fifteen minutes later saying that he found Mr. Frederick strangled. Naturally everyone thinks he did the strangling, and it takes some fancy lawyering from Pete Russlin, the family lawyer (who is in love with Janet) to get Cass declared insane and set up in a posh asylum. As the novel begins, Janet is determined to set Cass free from the asylum, but when her plan succeeds, more people start dying and everyone becomes a suspect, including Janet herself.
The mystery is good, with a satisfying twist that can't quite be predicted before the end of the book. The writing is crisp and all the loose ends are nicely tied up by the end. There are some slightly goofy scenes of romance, but nothing too sappy. Definitely worth reading.
[I don't know if you can see it on the little picture of the cover on this book, but check out the larger version: Someone stamped a "30 c" on the woman's face, her dress, and on the curtain above her. Then in each case they put a line through the "c" (making it a cents sign) and changed the "0" to an "8". Apparently they wanted this book to cost exactly 38 cents, even if they had to totally fuck up the awesome cover for it. Honestly, I would be more irritated at this if it was just stamped "30 c" since I find the "8" kind of endearing. Also I think I paid a dollar for this... Finally, the back cover is pictured here.]