Germany's FrankaPotente is to play the lead in Volker Schloendorff's long-gestating adaptationof Donna Cross' novel Pope Joan.

Cross'bestseller tells the story of Johanna von Ingelheim, who succeeded in enteringthe highest ranks of the Roman clergy disguised as a man and was elected Popein 853 - a story the Vatican claims is merely legend. The book spent months inthe bestseller lists in Germany when itappeared in 1996 and has since sold 4m copies.

Theinternational, English-language project will be produced by Constantin Film -currently at the top of the box-office charts in Germany, Austria and Switzerland withanother literary adapation, Tom Tykwer-directed Perfume: The Story Of A Murderer, based on the novel by Patrick Suskind -in co-operation with Ufa Film & TV Produktion.

Principalphotography for Pope Joan is expected to begin in May 2007 and, following astrategy adopted for the production of another successful Constantin title,Oliver Hirschbiegel's Downfall, theproducers will make a two-part TV version of Pope Joan in addition to thetheatrical film.

Earlierthis year at the Sofia International Film Festival, Schloendorff revealed hehad been scouting for locations of monasteries and other historical buildingsin Bulgaria for Pope Joan and had hoped to beginshooting in the summer. However, finding the right actress to play Joan hadevidently proven to be much harder than expected and the production was putback until 2007.

Schloendorff thus brought forward the French-Kazakh co-production Ulzhan which he had on the back burner.He began shooting at locations in Kazakhstan lastmonth with a cast including Germany's DavidBennent, France'sPhilippe Torreton and local Kazakh actress Ayanat.