Mostyn trained at Mountview Theatre School graduating with a BA (hons) in Performance.
Mostyn is making a happy return to Fiddler on the Roof having played Avrahm in the 2003 touring production. Other theatre credits include: Shore Patrolman in South Pacific (national tour); Perkins in Seven Brides for Seven Brothers (Theatre Royal Haymarket, London); Bobby in Cabaret (English Theatre, Frankfurt); Goddard in Let Him Have Justice (Cochrane Theatre, London); Dromio of Ephesus in The Comedy of Errors (national tour); Viceroy in Naked Flesh (Arts Theatre, Brighton); Cecil Cee in Jack and the Beanstalk (Grand Theatre, Wolverhampton); Gaveston in Edward II (Oval, London); Charles in Me and My Girl (Devonshire Park Theatre, Eastbourne); Sammy in Blood Brothers (Phoenix Theatre, London); Caleb in Seven Brides for Seven Brothers (national tour); Wolf in Babes in the Wood (Theatre Royal, Bath) and Annas in Jesus Christ Superstar (English Theatre, Frankfurt).
Recording and television credits include: Let Him Have Justice (TER); Blackpool (BBC); A Decline of Magic (Wodum); South Pacific (BBC Radio 2) and commercials for Pilsner and Honda.
Cabaret and concert credits include: South Pacific (Symphony Hall, Birmingham); Bobby and Victor (English Theatre, Frankfurt); Showtime (Dolman Theatre, Newport); Too 2 Much (Soho Revue Bar, London); A Musical Celebration (Queen’s Theatre, London); Bits and Bobs (Theatre Museum, London); The Talk of London (New Theatre, London).
Mostyn has worked throughout Europe as a resident director, Fiddler on the Roof being his 15th production.