Josie is living a good life in London. She has a job helping hurting people, which she finds very satisfying. She and her boyfriend Arun are living together in a nice apartment, making plans for the future. She is close to her mom, a highly renowned psychiatrist, and though she doesn't see her dad very often (he works in Manchester and spends his weeks there, only returning to London for weekends and holidays), she has always had a tight bond with him. It was a really good life. 

And then everything changed. 

When Josie got word that her father had been killed riding his motorcycle, she couldn't believe it. He was a capable rider, a smart man, and considered himself a strong Viking warrior. But he was no match for the wet, curvy roads during his final midnight ride. So Josie takes his keys and goes to check out his apartment in Manchester, to feel close to him again and see what needs to be done with his effects. 

Oddly, the keys she has don't fit the lock, so Josie breaks in, and she is quickly surprised to find a young woman living there, a young woman who looks shockingly like her. As the women talk, they discover that they are half-sisters, born just days apart in the same hospital. Their father had two families--Josie and her mom in London and Valentina and her mom in Manchester. As the two sisters get to know each other, their relationship creates issues in other areas of Josie's life. Valentina is definitely more of a free spirit, and her decisions start to effect Josie's relationship, her job, her financial security, and her family. And as Josie keeps digging at her family's past, what she finds could change everything for her and for everyone she cares about

The Good Sister is a twisty psychological thriller that is a roller coaster of family betrayals, lies, and secrets. Author Jess Ryder takes readers on a journey through layers of bitterness and deception, of resentment and pain, of mistakes and bad choices. Each chapter starts with information of the lives and families of the Vikings, and those tidbits are both fascinating and informative of Josie's and Valentina's relationships with their father, with each other, and with themselves. A top-notch story of family secrets and lies. 

Galleys for A Good Sister were provided by Bookoutre through NetGalley.com, with many thanks.