ROTTERDAM.- Staff at Witte de With, Center for Contemporary Art, Rotterdam, are baffled by the mystery that unfolded yesterday, when an artwork measuring 30 x 11m disappeared from its façade. “Between you and I” is a year-long collaboration between Witte de With and SKOR which presents four massive artworks mounted as billboard-sized banners on its building (located on Rotterdam’s cultural artery, the Witte de Withstraat). It is part of Witte de With’s ongoing Morality project, that sees a range of activities taking place inside and outside the art center, including two exhibitions that open this Friday. Yesterday, as the first artwork, “The Feast of Trimalchio” by Russian artist group AES+F was being removed from the building, the massive artwork was stolen from the pavement. Workmen were busy installing the second artwork, an image of the late Michael Jackson signed by German