Bethany studied Musical Theatre at BOA until 2016.

Since leaving BOA she has gone on to star in many television shows. She made her television debut in 2016 on BBC One soap Doctors.

As of 2022, Antonia played Lady Baela Targaryen in Seasons 1 - 4 of HBO series House of the Dragon. Other notable television credits include BBC series Get Even (2020), Netflix crime drama Stay Close (2021), ITV biopic Nolly (2023) and Doctor Who (2025)