Netflix's Danish crime drama series uses a great cast to unfold a gripping mystery. The mystery series follows one woman's search for the truth after the disappearance of her neighbor's au pair. Secrets We Keep takes place in a wealthy Copenhagen neighborhood where Cecilie and Mike lead an idyllic life with their son and their friends, Katarina and Rasmus. However, things quickly take a dark turn when Katarina and Rasmus's au pair, Ruby, disappears, and Cecilie finds that those closest to her are unwilling to help find Ruby.

As the impressive crime drama show unfolds, it becomes clear that Cecilie has stumbled into something that changes everything she believed about her community, her friends, and even her own family. Secrets We Keep explores the dark divide between the upper classes of Copenhagen society and the people that work for them through the cast's great, but chilling, performances that make it one of the best shows on Netflix. Secrets We Keep's ending does leave some ambiguity regarding what Cecilie will do next, and the complex characters will leave audiences thinking about the series long after it ends.

Marie Bach Hansen was born in Borum, Denmark in 1985, and she began her career in the film Kick'n Rush in 2003. from 2014 to 2017. She is also known for appearing in the Danish films Hvidsten Gruppen and The Last Vermeer. Hansen has appeared on the TV shows The Team, Hvide Sande, and Dansegarderoben.

Marie Bach Hansen plays the main character Cecilie in Secrets We Keep. Cecilie is married to Mike and is the mother of Viggo. When Ruby goes missing and her own au pair expresses concern, Cecilie begins to investigate the disappearance and learns some shocking, dark information about her seemingly idyllic community.

Simon Sears was born in Roskilde, Denmark in 1984 and made his first appearance onscreen in the 2009 short film Northern Lights. Sears has starred in numerous films and TV shows throughout his career, including Winter Brothers, Enforcement, Follow the Money, Ride Upon the Storm, Baby Fever, and Those Who Kill. He is likely best known to English-speaking audiences for .

Simon Sears appears in Secrets We Keep as Cecilie's husband, Mike. The wealthy couple lives in an upper-class area of Copenhagen, and while Cecilie is ready to help Angel search for Ruby, Mike is unhappy that his wife is questioning the status quo rather than siding with other people in their community by default. The pair is also friends with Katarina and Rasmus, whose son is the same age as theirs.

Danica Curcic was born in Belgrade, Serbia in 1985 and grew up in Copenhagen. She began acting in 2011, appearing in an episode of Those Who Kill and in the film Mike Hunt. Since then, Curcic has appeared in numerous other films, such as All Inclusive, Silent Heart, Out Stealing Horses, Murina, and The Bombardment. She has also starred in the series The Bridge, Nobel, Equinox, and The Chestnut Man, but .

Danica Curcic plays Katarina in Secrets We Keep. Katarina and her husband Rasmus are neighbors and friends of Cecilie and Mike, and it is their au pair, Ruby, who disappears. After Ruby's disappearance, Cecilie becomes suspicious of Katarina and her potential connection to the crime, as Katarina does not seem to want to look for Ruby.

Lars Ranthe was born in Copenhagen in 1969, and he appeared as Birger in the TV series Crash as a child. Ranthe reentered acting as an adult with the film The Bench, followed by numerous other film and TV roles since. He has starred in Minor Mishaps, Aftermath, Brothers, A Funny Man, and The Hunt. . He has also appeared in the shows Dicte, Badehotellet, Ride Upon the Storm, and The Chestnut Man.

Lars Ranthe appears as Rasmus, Katarina's husband, in Secrets We Keep. Rasmus and Katarina employ Ruby, who cares for their son, Oscar. After Ruby's disappearance, Cecilie wonders whether Rasmus could have been involved in what happened to her.

: Excel Busano appears as Angel, Cecilie's au pair who cares for her son Viggo, and does most of the household work. Angel is also Ruby's friend, who is one of the only people willing to look for Ruby. Secrets We Keep is Busano's first TV appearance.

: Sara Fanta Traore plays the detective, Aicha, in Secrets We Keep. She helps Cecilie look into Ruby's disappearance, though it becomes clear most people are not very invested in the investigation. Traore is best known for appearing in Empire as Petrine and as Trine in The Nurse.

: In Secrets We Keep, Lukas Zuperka plays Viggo, the son of Cecilie and Mike. He is also friends with Oscar, and the two boys become suspicious as the series progresses and more information about their behavior is revealed. Secrets We Keep is Zuperka's first acting credit.

: Another newcomer in Secrets We Keep's cast is Frode Bilde Ronsholt, who appears as Oscar. Oscar is the son of Katarina and Rasmus, and he is under the care of Ruby before she goes missing. Trying to protect her own son in the process, Cecilie becomes increasingly wary of Oscar and Viggo spending time together.

: Dona Levkovski appears as Ruby throughout Secrets We Keep. Ruby is the missing au pair that the series revolves around. Prior to her disappearance, she expresses concern for her safety to Cecilie, who is unsure of how to intervene. Ruby is also friends with Angel. The Netflix series is Levkovski's first acting credit.