As the Purple Lotus drinks in all the fairy dust in the world, affecting both fairy and elf magic, only Tri-ling magic remains untouched. Seeking an "off switch" to the Purple Lotus, the Bureau uses the Temporalis to visit Magnus Sorenson at his private fund-raising soiree in 1919 and take his Lost Temple documents (excluding Lily and Rusky whose wings might pop out, but including Peter wearing the enchanted super-speed tuxedo of Agent Swift, which only gets him mistaken for a waiter at the party).
—statmanjeff