King Charles III is a 2014 play in blank verse by Mike Bartlett that premiered at the Almeida Theatre in London.

The play is a future history account of the accession and reign of King Charles III of the United Kingdom (who was then still Prince of Wales), and the limiting of the freedom of the press after the News International phone hacking scandal.

[1] Charles was played by Tim Pigott-Smith,[2] whilst the cast also included Margot Leicester as Camilla,[3] Oliver Chris as Prince William, Lydia Wilson as Catherine, Richard Goulding as Prince Harry,[4] Adam James as the Prime Minister and Nicholas Rowe as the Leader of the Opposition.

[9] The play transferred to Broadway for a limited engagement with the original London cast, running at the Music Box Theatre from 1 November 2015 until 31 January 2016, following previews from 10 October 2015.

[1] A newly mounted production of the play directed by David Muse with Robert Joy as Charles began 7 February 2017 at the Shakespeare Theatre Company in Washington D.C.[12] A production of the play by the UCL Drama Society, directed by Josh Moore, with services provided by UCL Stage Crew, was performed at the Bloomsbury Theatre on 17–19 November 2022, shortly after real-life Charles' accession to the throne.

Charles increases the army guard at Buckingham Palace, offers his protection to Jess (whom the press have made the centre of a sex scandal), and agrees to Harry's wish to become a commoner.

Ultimately, Charles is forced to abdicate in favour of William, who plans to sign the press bill and restore the status quo between king and Parliament.

The author talks about how some aspects in this futuristic play came true, like how Prince Harry ends up happy with his new spouse Meghan Markle, who like Jess is a woman of colour, or how the real King Charles III is known to express strong opinions on government issues.