Kathleen Hanna, lead singer of the punk band Bikini Kill and dance-punk trio Le Tigre, rose to national attention as the reluctant but never shy voice of the riot grrrl movement. She became one of the most famously outspoken feminist icons, a cultural lightning rod. Her critics wished she would just shut-up, and her fans hoped she never would. So in 2005, when Hanna stopped shouting, many wondered why. Through 20 years of archival footage and intimate...