Kane was born on 9 August 1990 in Claremont, a suburb in Perth. Her father is Scottish (from Glasgow) and her mother has Scottish, Irish, and French ancestry. She grew up in Perth, Western Australia and attended St Hilda's Anglican School for Girls. She has a brother named William, who is three years younger. Her parents divorced when she was seven, and Adelaide and her brother were raised by their single mother. When she joined the cast of Neighbours, she and her mother moved to Melbourne, Victoria, while her brother and stepfather remained in Perth. She also lived for a short period in New Zealand, while shooting children's television series Power Rangers RPM.
Kane started performing at the age of 3, starting with dance and then moving to singing and acting. At the age of 6 she started working professionally in some print ads, later moving to TV spots and works in various children's TV shows. Kane was picked to join the cast of Neighbours as Lolly Allen after she entered a competition run by Dolly magazine in 2006. She was given a three-month contract with the show, and left her class at St Hilda's Anglican School for Girls to move to Melbourne, where Neighbours is produced. Her friends convinced her to enter the competition, but she didn't think she was actually going to get the role. In December 2006, Kane announced that she would be leaving the show after her contract was not renewed. At the time of the announcement Kane had not yet appeared as Lolly.
From March to December 2009, Kane portrayed Tenaya 7 on Power Rangers RPM, part of the long-running Power Rangers franchise. In April 2010 Kane starred in the television film Secrets of the Mountain on NBC. In 2010 Kane also starred in the Hulu series Pretty Tough, composed by 20 episodes and based on the novel by the same name written by Li Tigelaar. In 2010 Kane travelled to attend an audition for Cartoon Network's first live action series Unnatural History, for the role of Maggie Winnock. She and Italia Ricci were the actresses selected for the casting; the role later went to Italia.
In 2012, she portrayed Aubrey in the movie Goats. On November 28, 2012 it was announced that Kane had joined the cast of Teen Wolf as Cora Hale.
In February 2013, Kane was cast as Mary, Queen of Scots in the CW period drama series Reign. The same year, she appeared in the successful thriller film The Purge.
In 2014, Kane appeared in horror movie The Devil's Hand as Ruth. She originally auditioned for Alycia Debnam-Carey's role, but producers thought she wasn't right for the part, so they offered her Ruth who got more along with her personality. Kane starred in Scott Speer's short thriller film Realm in 2015, which is set to become a full-length film with a release date in 2016.
In June 2016, Kane stars in the third season of Dragons: Race to the Edge in the role of Mala, Defender of the Wing.
In July 2017, Kane joined the hit ABC series Once Upon A Time in a recurring role for it's softly-rebooted seventh season. Kane was one of five actresses to join the series for it's new season in starring and recurring roles, following the exits of six key cast members at the end of its sixth season. It was confirmed at the 2017 San Diego Comic-Con that Kane will be playing Drizella, one of Cinderella's wicked stepsisters.