Phyllis and Sharon were arguing after the photo shoot, and Dru saw what was going on. She went over to help Sharon out. Phyllis went to call someone (maybe Jack or Victoria) and tell them about Sharon and Brad's affair, and Dru went to grab the phone. Sharon helped. Next thing you know, Dru fell off the cliff, and Sharon was going over too, but she was able to hold on. And they showed Dru going all the way down, and Lilli was screaming.
What an ending.....
I did hear that Victoria Rowell who plays Dru was leaving the show, and they were looking for a recast. I sure hope they don't kill her off. OMG.....I like the character of Dru!