Ida Praetorius' dance bag is filled with hand-me-downs. The Royal Danish Ballet principal likes her warm-ups to come with a backstory. "It's what I wear all day. I never wear my normal clothes, so I like bringing the people I love with me," she says. Like most of what Praetorius carries, her striped legwarmers were handed down from a colleague in the company. "I borrowed one from a friend while in rehearsal for Christopher Wheeldon's Alice's Adventures in Wonderland, and then the next day when I went to give it back to him, he gave me the other one instead," says Praetorius. The frayed blue Repetto overalls that she wore throughout rehearsals for her recent performances at New York City's Joyce Theater are a last-minute addition to her collection. Praetorius snagged them from fellow principal Kizzy Matiakis, her dressing-room mate back in Copenhagen. "I love her wardrobe, and tend to steal from her," says Praetorius. "I just said, 'I'm going to New York!' and I grabbed a bunch of her stuff."