[2] His theatre work includes the multi award-winning Merrily We Roll Along[5] and Grand Hotel[6] for Michael Grandage at the Donmar Warehouse; Annie Get Your Gun for Richard Jones at The Young Vic;[7] Michel Legrand's Marguerite at the Haymarket for Jonathan Kent;[8] King Lear for Yukio Ninagawa at the RSC;[9] Butley at the Booth Theatre on Broadway opposite Nathan Lane;[10] Death Takes a Holiday for The Roundabout Theatre Company in New York;[11] A Woman of No Importance for Adrian Noble at the Haymarket;[12] Finding Neverland for The Weinstein Company;[13] the Parisian premiere of Sunday in the Park with George;[14] Show Boat at the Lincoln Center in New York;[15] My Night with Reg at the Donmar Warehouse;[16] Ivo van Hove's All About Eve at the Noël Coward Theatre opposite Gillian Anderson;[17] and South Pacific at the Chichester Festival Theatre.

[21] Ovenden first appeared on British TV in a recurring role over five seasons of Foyle's War opposite Michael Kitchen.

On US TV, Ovenden was a recurring cast member in Person of Interest (Jeremy Lambert) for three years.

Recently he has portrayed Robert F. Kennedy in The Crown and is starring as William de Nogaret in Knightfall.

Ovenden's film work includes Colonia opposite Emma Watson and Daniel Bruhl, The Confessions with Daniel Auteuil, Toni Servillo and Connie Nielsen and British indie war film, Allies (Captain Gabriel Jackson).