**_Dull Italian “Jaws” knockoff with a few interesting bits_** When several people mysteriously turn-up dead off the coast of San Diego, a killer whale trainer (Bo Hopkins) suspects it’s due to the high frequency ultrasonic soundwaves used in building an underwater tunnel. Claude Akins is on hand as the sheriff. “Tentacles” (1977) is an Italian production inspired by “Jaws” with several notable American actors to sell it. Henry Fonda’s part is a glorified cameo while John Huston’s role is negligible. A boring subplot featuring Shelley Winters is obvious padding. Bo Hopkins thus carries th...