She is also known for her roles in the crime drama Red Rock (2015–2019), the film Rose Plays Julie (2019), and the HBO series The Nevers (2021).

[2] Skelly began her acting career in 2015 when she made her television debut in the serial crime drama series Red Rock as Rachel Reid.

[5] In 2018, Skelly starred alongside Jamie Dornan and Matthew Rhys in the historical drama miniseries Death and Nightingales, based on the 1992 novel of the same name by author Eugene McCabe, where she played the lead character named Lady Ethelfled, a stepdaughter to Billy Winters and a daughter of Catherine Winters, she was nominated for the Best Actress in a Lead Role – Drama in 2021 Irish Film & Television Awards.

[6][7] From 2018 to 2019, she had a recurring role in the historical drama series Vikings as Lady Ethelfled, the daughter of Lord Cuthred and was the wife of Prince Aethelred.

She starred in the 2019 drama film Rose Plays Julie directed by Joe Lawlor and Christine Molloy, which was released on 3 October 2019.