Like her directorial debut Twelve Nights, Twelve Days depicts 12 scenes of a tumultuous marriage, from its blissful beginning through its bitter collapse. On day one, Jeannie and Simon seem to have the makings of a perfect marriage, but the following 11 vignettes reveal the various conflicts, both big and small, that slowly eat away at their bond. Love may build a marriage, but Twelve Days shows that reality can just as easily shatter it.

Story follows Guy and Heidi five years into their relationship and faced with a serious dilemma: Whether or not it is time to marry and form a family. They're equally in love, and their relationship is going strong. But while Heidi is ready to settle down and believes that marriage is proof of one’s everlasting love, Guy holds the belief that marrying Heidi will result in him being tied down to a woman that he will one day grow distant from. Heidi consults her girlfriends for advice, and Guy consults the guys. What follows is an outright battle of the sexes, as Heidi plots devious ways of getting pregnant—with marriage as an end goal—as quickly as possible, and Guy schemes up a handful of contraceptive counter-strategies.

Mr. K.K. Ho (starring Vincent WONG), is a leading “star tutor” with remarkable achievements. Lee Lung Kei (starring Hugo NG), the stingy boss and principal of the cram school, regards Mr. Ho as a trump card. Chloe (starring Jennifer YU Heung Ying), a traditional high school teacher, has always tried her best in teaching. Chloe despises K.K.’s teaching methods and refers to them as deviant. The two of them give tit for tat in class. Their conflict leads to K.K.’s appreciation for Chloe. He gives her flowers as an apology, but Chloe never accepts. He finds out Chloe is the daughter of Principal Lee. When she was young, she witnessed her mother being bullied and died by accident.

Veteran detective Cham works with rookie cop Will to hunt down the city's serial killer. The investigation leads them to a lair littered with dismembered female limbs, and an ex-con who killed Cham's wife and child years ago...

Jing's day begins with a graceful tracking shot that follows her from the early morning as she pumps breast milk, leaves her baby with her mother-in-law, and heads to the bakery where she works.

Chi is a lousy real estate agent who muddles through life. Growing up, his mother has always told him to lead a simple life, until he reunites with his primary school P.E. teacher, Mr Wong. Mr Wong, who’s been increasingly ill, wants to keep his promise to his late wife to finish a 10k race; At the same time, his student, an overweight student called Tin Sum aims to finish her first ever 5k race just so she can run with her idol. As Mr Wong and Tin Sum fight for their goals, Chi, discouraged, stands at a crossroad and roams aimlessly in life. Until one day, memories from 20 years ago light up Chi’s world. For once in his life, Chi swears to cheer himself on.

The matter of growing, which we always understand afterward, is driving us far away enough to not having a good farewell. The story begins with a day that Hong Kong experiences a magnitude 4.5 earthquake. It brings almost no impact to the city but a beautiful yet untouchable year to a form-one boy name Kwok Pak Chi. Due to the unadaptable school life and his introspective character, he starts to imagine animals escaped from the earthquake as his friends. However, the more he immerses in his fantasy, the more he is pushed by the reality. With the pressure from his unsatisfying homework, schoolmates’ opinions and caring from others, how should Pak Chi confront himself and his imaginary friends?

Cheung Sung-bong is a highly respected cop with a long history of success in dangerous cases. However, his past soon comes back to haunt him when a former protégé resurfaces, seeking revenge.

After years of illness, Ken’s wife finally passes away. Ken returns to his job as streetlight repairman after the funeral. Having to work at night, he rarely sees his daughter Ann, who develops a fear for darkness since her mother dies. Often left alone at home, she learns to grow up at a tender age. She makes her father agree to go out and play with her on the night of Mid-Autumn Festival, but Ken breaks the promise because of work. During the festive season, father and daughter try hard to re-capture moments of love and concern for each other.

Kam Muiday (Elaine JIN) has long been asking her granddaughter Sunnie Lam (CHUNG Suet Ying) to buy the same set of lucky numbers in each Mark Six lottery ticket for years. However, fate played a cruel trick. During the Lunar New Year’s "Snowball Draws", Sunnie was unable to place the bet, and that set of lucky numbers won a jackpot of HK$ 88.88 million. Not wanting to shatter grandmother's dream, Sunnie borrowed a villa from her filming colleague Jay Lai (Edan LUI), claiming that it was purchased with the winnings. Sunnie's father, Ken Lam (Jiro LEE), mother Charlotte Tong (Harriet YEUNG), and younger brother Harry Lam (LI Hoi Lam Marek), moved into the villa with her grandmother. Living together under one roof gradually healed their once-distant relationships and brought them closer. However, an unexpected incident ultimately revealed this well-intentioned "villa lie"...