Mermaid in Vegas

Brutal casino boss Roberto Stiglioni already has Frank, Dean and the rest of the Rat Pack wowing the rubes in his Vegas casino. When he happens to entrap a mermaid while drowning a casino cheat, he knows just what to do: build a tank in an exclusive club and serve her up as entertainment. Left to the guidance of his own moral compass, casino detective Tom Blinder could overlook the mermaid's plight.
If set free, she'll go right back to leading sailors to their doom. He can convince himself that it's better to leave the mermaid where she is. That's not a sentiment shared by his wife, Betty, nor by the casino cheat's sister, who is eager to settle her score with Stiglioni. Together they convince Blinder to help liberate the mermaid. The three concoct a scheme to kidnap the mermaid and return her to the sea.
Their plan ends in a bloody beach showdown with Stiglioni, Frank and Dean.