Dancers in the Brazilian folk celebration Bumba-meu-boi once performed in simple, repetitive, and predominantly circular movements. This structure promotes multigenerational participation, increases community interaction, and maintains a semi-intact historical legacy. Nevertheless, many groups are currently adopting choreographic steps and patterns familiar from popular entertainment culture and urban Carnival celebrations. This evolution is uneven, with many of the nearly 300 groups that perform in the federal state of Maranhão maintaining the older practices. Nevertheless, for groups embracing modern entertainment values, greater appeal to tourists and general audiences comes at the cost of the traditional form and content of the celebration described by field researchers only two or three decades ago. Gender presentations have been particularly affected, with the increased use of elaborate and skimpy costumes, younger and more athletic performers (mostly young women), and professionalized musical support. These changes are part of the modernization and urbanization of the festival, and they create an ambivalent dialectic in which women appear increasingly as leaders and major performing figures, but also as chorus line bodies with minimal narrative function. Our research includes visual documentation from several years of field research in Sao Luis (Maranhão), Brazil, available online at http://simoneferro.com. Albums of still photography are available at http://meredithwwatts.com.