Groundsell was born in Bristol, England[1] and grew up in Ness on the Isle of Lewis in the Outer Hebrides until she was nine.

[3] In 2015, Groundsell made her feature film and stage debuts as Sarah in Iona and Amy in Stain at the Edinburgh Fringe Festival respectively.

[5] The following year, she starred as Jane Muncie in the ITV true crime miniseries In Plain Sight.

Groundsell played Elizabeth Smith in the first series of the BBC Three thriller Clique.

[6] In 2018, Groundsell starred in leading fantasy roles in the Netflix series The Innocents as well as the independent film Far From the Apple Tree.