As the only daughter of the Merrick family, Kirsty Merrick bears the responsibility of marrying into the prestigious Bartley family to lead the Merrick family to new heights, as carefully orchestrated by her mother Evanna Taylor. Kirsty successfully secures a betrothal with Morgan Bartley, the playboy son of the Bartley family's second heir. Unknown to Kirsty, Morgan has been secretly involved with Jess Merrick, Kirsty's only friend who grew up with her in an orphanage. Years later, when brought back to the Merrick family, the kindhearted Kirsty could not bear to abandon Jess, and thus pleaded with her parents to take Jess in as well. Now, Jess has begun an affair with Kirsty's fiance Morgan. To get back at Morgan, Kirsty designs a plan to seduce and intoxicate Nicolai Bartley, the young CEO of the Bartley Group, leading to the start of a dangerous "underground affair."
