Bo Derek is promising to show off her tough side when she plays a tough fashion boss in her new TV soap SECRET PASSIONS - by fighting with her son's girlfriend. The 10 star will play bitchy MARIA ZIANNI on the new show, which will debut in America later this year (SEP06), and she insists her catfights with her co-star will make Joan Collins and LINDA EVANS' DYNASTY squabbles look tame. In the first episode Derek's character will fight with her daughter-in-law-to-be in a water fountain. She says, "And it won't stop there... We're gonna have a catfight that ends all catfights."