Jane and Maura investigate the stabbing death of Denise Ryan, who stumbled onto the stage at her daughter Dakota's dance competition with a pair of scissors in her chest. According to the dance studio owner, Coach JJ, Denise wasn't like the other moms and didn't get to know her very well even though Dakota has been going there for two years. The husband is eliminated as a suspect but the police responded to a disturbance at the dance studio two weeks ago when two of the other moms, Yvonne and Kim, got into an argument. When they learn that Denise had no credit history...