Eo Yong-Mi (Yum Jung-Ah), An In-Kyung (Jeon So-Min) and Maeng Soo-Ja (Kim Jae-Hwa) work as cleaning ladies at a brokerage company. Eo Yong-Mi raises her two daughters by herself and she struggles to make a living. An In-Kyung dreams of buying a food truck to run a mobile cafe business. Maeng Soo-Ja seems like a very sociable person, but she is only friendly to people when she needs them. These 3 cleaning ladies happen to overhear insider information at their workplace. They invest their money on a stock, using the insider trading information.