Final answer:
The group dance "Electricity" took place in Season 2 of Dance Moms during the episode "Everyone's Replaceable". It was known for its contemporary style and controversial costumes.
Step-by-step explanation:
The group dance "Electricity" happened in Season 2 of the reality TV show Dance Moms. It was featured in the episode titled "Everyone's Replaceable" which showcased the Abby Lee Dance Company's junior elite competition team performing a contemporary piece.
The performance was notable for its dynamic routine and edgy costumes, sparking some controversy among the moms and audience members.