The love story of Niki de Saint Phalle and Jean Tinguely is one for the ages. She created exuberant sculptures of liberated women in riotous color; he assembled pulleys, wheels, levers, and springs into kinetic sculptures, witty yet existentially ominous. They met in Paris in 1955—both married to others at the time. By the 1960s, divorced and living together, they were collaborating closely. “Each of us was constantly pushing the other,” Saint Phalle wrote to Tinguely after his death. “It was an extremely fruitful, spiritual relationship. But the greatest thing you ever gave me was belief in my work.” This exhibition reunites their art through the lens of one of their earliest and most devoted champions—Pontus Hultén (1924–2006), the founding director of the Centre Pompidou. —Elena Clavarino