Sua descrição é uma correspondência razoavelmente próxima a As caixas por William Sleator. Da Amazon.com:
Annie's Uncle Marco goes on one of his mysterious trips, leaving her in charge of two sealed boxes on one condition: she must not open either one while he is away. But she is tempted...and soon she has unleashed the unspeakable. The creatures inside the box are crab-like and grotesque. And they possess a power Annie could never have imagined: the power to transmute time.