The Prince of Wales made a surprise appearance as Hamlet in the star-studded Shakespeare Live! on BBC Two, filmed in the Bard's birthplace in Stratford-upon-Avon.
He shared the stage for a funny skit about Hamlet with renowned actors including Dame Judi Dench, Sir Ian McKellen, Benedict Cumberbatch and David Tennant.
Comedian Tim Minchin also added some mirth and Dame Judi had one of the wittiest lines: "It is I, Hamlet the Dame!" she declared.
There was also a running gag about Eddie Redmayne with Sir Ian saying to Benedict: "Eddie Redmayne! I loved you in The Danish Girl!"
Charles, who had been watching the Shakespeare Live! from The Royal Shakespeare Company show with the Duchess of Cornwall, was heard to speak from the wings, asking: "Might I have a word ... "
Then followed the opening lines to what is one of Shakespeare's best-known soliloquys: "To be or not to be, that is the question."
Fans watching could scarcely believe their eyes and many posted their thoughts on Twitter.
-- Hannah Louise (@ihannaaah) April 23, 2016
Can't believe Prince Charles just upstaged a Dame, a Sir, a Cummberbatch and a Tennant #RSCLive
-- Ali Jones (@radioalijones) April 23, 2016
-- Nina Cook (@NinalouCook) April 23, 2016
-- Helen Treharne (@Tea_Talks) April 23, 2016
Of all the advancements in TV, the leap from It's a Royal Knockout to Prince Charles on #RSCLive might just be the most extraordinary.
-- herichards (@hellizzie) April 23, 2016
Best. Sketch. Ever.
-- Beth Garlington (@BettyGarli) April 23, 2016
-- Jo (@joeyroo) April 23, 2016
The Hamlet Skit seriously just made my night OMG ??? Cumberbatch, Tennant, McKellan, Dench and Prince Charles all on one stage ?? #RSCLive
-- Nance Harrington (@atharriordan) April 23, 2016
Cumberbatch, Tennant, Mckellen and Dench
Oh, damn.. Too much tooo much force in one stage!
-- Badriya S. Al-Hajery (@BH07_) April 23, 2016
#RSCLive this is incredible! Stunning Hamlet sketch with Benedict Cumberbatch, Judi Dench and David Tennant!
-- Rebecca Bullamore (@cool19bex) April 23, 2016
-- Saleena Rani (@Seen_Been) April 23, 2016