The comedy star was best known for his role as Barney Lumsden in satires Twenty Twelve and W1A.
W1A star Alex Beckett has died suddenly at the age of 35, his agent has announced.
The comedy star was best known for his role as Barney Lumsden, from Perfect Curve PR, in TV satires Twenty Twelve and W1A.
“We’re deeply saddened by the loss of Alex – a wonderful man and a hugely talented actor,” his agent Gavin Denton-Jones said.
“Our thoughts are with his family and we kindly ask that their privacy be respected at this difficult time.”
The Welsh-born actor was currently starring as the character Waitwell in The Way Of The World at London’s Donmar Warehouse.
The Donmar Warehouse said it was “with profound sadness that we announce the sudden death of actor Alex Beckett”.
Its artist director Josie Rourke and its executive producer Kate Pakenham said: “We are deeply shocked by the tragic loss of our dear friend and brilliant actor Alex Beckett, a much-loved member of The Way Of The World company. Our thoughts are with his family and close friends at this incredibly sad time.
“Everyone at the Donmar and The Way Of The World company are completely devastated by this terribly sad news.”
They said: “We have taken the decision to cancel the remaining performances this week, as a mark of respect to Alex, and to give some time to the company, who all loved Alex as a fellow actor, and a friend.”
W1A star Jessica Hynes expressed her sadness on Twitter, writing: “Alex Beckett was a wonderful, clever, kind, brilliant person – so glad to have known him, so sad he is gone.”
Shane Allen, controller of comedy commissioning at the BBC, said: “We’re all incredibly crushed to hear of Alex’s untimely death.
“He was a very prolific, versatile and much-admired comedy star whose role as Barney Lumsden in both Twenty Twelve and W1A was a key ingredient of their success.
“We think of him fondly and our hearts go out to his family and friends at this painfully sad time.”
W1A star Rufus Jones wrote on Twitter: “Just hearing this awful news about Alex Beckett. He was such a warm-hearted and funny, funny guy.
“W1A felt like a big family and he was a face you couldn’t wait to see. My thoughts with his family xx.”
The Royal Court Theatre’s artistic director Vicky Featherstone tweeted: “A deeply wonderful man and actor. Our hearts are broken.”