Zeynep meets young businessman Kenan at the wedding of childhood friend Taylan, for whom she was a wedding witness. Despite their polar opposites, a strong attraction develops between the two. At the same wedding, her best friend Murat, whom she has loved since childhood, proposes to Zeynep.

Zeynep's father Ahmet has invested the last of his savings in a business without the family's knowledge. A series of setbacks lead to the business failing, and the family is deep in debt. At this point, Zeynep also quits her job. Thanks to Taylan, she finds a new job at Kenan's company. The diary Zeynep finds in the basement, belonging to the previous owner, holds the key to a profound secret.

Before Zeynep has a chance to talk about the notebook she found, Kenan finds it and starts reading it. Murat, while discussing Şevval and Ayşe, learns that Kenan is her sister and that the person he thought was his mother isn't.