Possible Clues:

• Anti-art movement put obstruction round podium
• Early twentieth century art movement
• Ernst's movement
• Absurd movement from mother crossing platform
• Museum supervisor is initially having posters put up for art movement
• Barrier put around platform for artistic movement
• Movement of platform restricted by barrier
• Early 20th-century movement in art, literature, music, and film
• Nihilistic art movement of the early 20th century
• Crazy about securing platform for Man Ray's form of art