24-year-old Li Wei works eight jobs a day, thin as a monkey, and back home he can't even bear to eat a plate of scrambled eggs—his own sister scolds him for bringing home only a few coins. His father died in a car crash, a million-yuan mortgage crushes the family, and he alone carries it all. Then a turning point: a gold-foil card left behind at a five-star hotel—"The Million-Dollar Prize: Ultimate Family Chemistry Challenge, grand prize one million." He slams the table and talks the whole family into signing up. When the spotlights come on, he realizes: Mom, his older sister, and his younger sister are strapped to a wooden wall, their breasts and lower bodies fully exposed through holes. The so-called chemistry test is that virgin Li Wei must use his cock to identify his own family members' bodies. The holes are hot, wet, and soft; the moment he pushes in, his family trembles faintly... Can he still tell them apart in this challenge?