Excitement was running high yesterday when rehearsals began for Wicked.  Wendy Tuohy reports. "Everyone's reality is rather heightened," says John Frost, co-producer of blockbuster musical Wicked, as his stars and chorus wander into the rehearsal room.     "All the creative team have arrived from America and all the cast are together for the first time," he says, apparently hardly believing his eyes.     It is day one of rehearsals for the $12 million show and the stakes are high.  But judging by the energy in the atmosphere and the beautiful sound his 32-member cast projects without microphones, Frost is on to a pretty good thing.     His stars are just as tingly.  "Today is a mix of completely surreal and real," says Lucy Durack, who plays Glinda the good witch.     Says Amanda Harrison, who plays Elphaba the wicked witch: "There is definitely pressure -- enormous pressure.  This show is so well-loved and known."     The stars are surrounded by upbeat young ensemblers and imported creative staff.  Their job is to make each Wicked show identical.     One of the many US staff just landed is associate scenic designer Edward Pierce from New York.  He surveys the perfect model of theatrical rig and describes how "monkeys" will fly over the crowd.     All the work put into the $2 million set, including its centrepiece "Time Dragon", which breathes smoke and flaps will pay off for audiences, he says.  "There will be a lot of little moments which are very magical."     The show's New York-imported director, former chorus-liner Lisa Leguillou, watches with loving eyes as the cast do two numbers.     For Leguillou, the magic springs from the relationship between Glinda and Elphaba.     The storyline, adapted from Gregory McGuire's novel, follows the fortunes of the witches in Oz before Dorothy arrives.     "One of the things I love about it is there aren't many stories on Broadway about two women," says Leguillous, who was encouraged to direct by actor and US Wicked director Joe Mantello.     "What is's about is love and tolerance."     Leguillou is thrilled with the cast.     "I feel like both the leads just walked in the door," she says, as Durack and Harrison light up the room with songs.