Rowie Holly Harper’s rookie season with the Boston Fleet began the way all big dreams do: with a single step onto unfamiliar ice, heart racing, family watching from the stands.

She was twenty-two, fresh off a national championship at Denver, drafted first overall—the first Kane to wear that honor. The weight of it settled on her shoulders like a well-fitted jersey: heavy, but hers to carry.

Pre-season camp was intense.

Rowie arrived in Boston in late August, moving into ...