At the annual Beverly Hills Garden & Design Showcase opening Friday at the historic Greystone Mansion, visitors will see enough animal prints, arresting artworks and hand-painted wall treatments to make the 55-room, 1928 English Gothic estate feel absolutely contemporary. Nicholas Hertneck of Piper Hertneck Design took on the eclectic home office, the room where original owner Ned Doheny was found slain. A portrait by Johniene Papandreas hangs over a display of ceramic hands.