Go Eun Nim is in a desperate situation. Struggling to support her poor family and sick father while studying to become a teacher, she's running out of options. Baek Sae Hoon is the oldest son of the Hoon family and stands to receive all the family inheritance, but he and his wife cannot conceive a child. Resorting to surrogacy, the couple goes to Eun Nim with a proposal she cannot afford to refuse. Sae Hoon's younger brother Baek Kang Ho, meanwhile, is the bastard child of an affair their father had, and his stepmother despises him as a result. Eun Nim thinks that carrying their baby will be where her connection to the Hoon family ends, but unexpectedly she and Kang Ho begin to fall in love.

Baek Sae Hoon and his wife, Lee Sun Young, desperately try to conceive a child but are unsuccessful. Sae Hoon's mother goes to Sun Young and asks that she consider surrogacy as a way of conceiving a child without Sae Hoon's knowledge. This is where Go Eun Nim comes in. She is their surrogate mother carrying their child but things become complicated when she later falls in love with Sae Hoon's younger brother, Kang Ho.