Jonathan Ross’ agent, Addison Cresswell, passed away in his sleep on Sunday night aged just 53 years old
The representative, who has worked with some of the circuit’s best known stars including Lee Evans, Jo Brand, Alan Carr and Jack Dee, is thought to be one of the most influential people in the comedy industry.
He was an entertainment officer at Brighton Polytechnic where he studied when he decided to start up his management company Off The Kerb 32 years ago. He later went on to set up his first production company, Wonderdog Productions, with Julian Clary and Paul Merton.
Many of his clients spoke of their shock and sadness at his sudden passing.
Jenny Eclair took to Twitter to post: "Stunned and shocked by news of Addison Cresswell's death, he was there at the beginning for so many of us, love to his family and friends."
Similarly, James Corden posted his tribute via the social networking site, tweeting: "Such sad news. An incredible man. An incredible talent. May he rest in peace x."
Omid Djalili tweeted: "Shocking news about Addison Cresswell. 52. Way too young. I miss the headlocks already RIP"
A spokesman said: "Addison will be fondly remembered by all whose lives he touched as a devoted mentor, a dear friend and an unforgettable character. He will be sorely missed.
"He leaves behind a proud legacy in his tireless charity work, initiating and organising the annual Channel 4 Comedy Gala in aid of Great Ormond Street hospital. It was his dearest wish to raise enough to fund the opening of a brand new wing of the hospital, a goal that is now in sight."
He is survived by his wife Shelley.