Double Fattiness (1988)

Siu-Fung (Lydia Sum), an owner of a pizzeria, unexpectedly succumbs to a heart attack. However, her spirit was unable to cross over to the other side, thus, she resurrects into the body of a young woman (Maggie Cheung). Afterward, she reunites with her family and tries to convince them that she is alive. Yet, the plot thickens when a woman, unrelated to the family and is physically identical to Siu-Fung, appears, and Siu-Fung's husband (Bill Tung) thinks that that woman is his wife.