PROTECTING the PRICELESS

Late at night on March 18, 1990, two thieves dressed as police officers — one of them bold enough to sport a false mustache made of wax — talked their way past security guards at the Isabella Stewart Gardner Museum in Boston. After handcuffing the hapless guards, the pair made off with a half-billion-dollars’ worth of paintings by Rembrandt, Degas, Vermeer, Manet, and other artists. The still-unsolved heist is among the largest thefts of property in world history.