Welsh actress Sarah John was raised in Caerphilly, South Wales as the eldest of two siblings. She took to dance and drama at a young age and competed internationally in Latin American dancing from the age of 10. She began her education at the Welsh language secondary school Ysgol Gyfun Cwm Rhymni and subsequently went on to study acting at the Oxford School of Drama. Sarah's breakthrough stage role was in Little Dogs with the National Theatre of Wales and Frantic Assembly. In 2014, she made her TV debut playing series regular Jess in Lemon La Vida Loca for ITV2 alongside Keith Lemon. In 2021, Sarah was cast as Eleri in Ian Puleston-Davies' feature Bolan's Shoes for Buffalo Dragon.