Behind the scenes of Jeff Koons’ massive retrospective at the Whitney Museum, which opened Tuesday with a VIP reception, collectors were clamoring to ensure their Koons pieces were in the show.

“When Jeff makes sculptures, he can create five different unique versions in different colors,” said an art insider, “and everybody wanted theirs in the show,” which took nearly five years to mount.

One collector whose Koons made the cut was LA’s Bill Bell, who with his wife Maria Bell snapped up the artist’s “Play-Doh” sculpture on the spot some 20 years ago when it was just a model. But the Bells didn’t actually see the two-decades-in-the-making work until Tuesday night when Koons’ show opened.

Maria was again spotted at a luncheon Wednesday hosted by Larry Gagosian at the Sea Grill in celebration of Koons and the unveiling of his 37-foot “Split-Rocker” in Rockefeller Center under 50,000 flowers.

Also on the scene: Eli Broad, Agnes Gund, Richard Prince, Brice Marden, Dan Colen, Jeffrey Deitch and Public Art Fund president Susan K. Freedman.