A legendary comedic star on British television who was known for his improvisational talents has sadly passed away.

Tony Slattery, best known for his years of work on the original British version of the "Whose Line Is It Anyway?" comedy improv show, died on Tuesday at the age of 65, according to the BBC.

His death prompted an immediate outpouring of condolences, tributes, and fond memories from many of his fellow actors and comedians.

Dead following a heart attack

The sad news of Slattery's passing was first shared in a statement released by his longtime partner in comedy and life, fellow actor Mark Michael Hutchinson.

Hutchinson said, "It is with great sadness we must announce actor and comedian Tony Slattery, aged 65, has passed away today, Tuesday morning, following a heart attack on Sunday evening."

That statement led to many of Slattery's friends and former colleagues expressing their heartfelt sadness at the loss while heralding his incredible talents, brilliant wit, and general niceness.

Discovered his love of acting and comedy at Cambridge

Per the BBC, Slattery was born in North London in 1959 and earned a scholarship to attend Cambridge University, ostensibly to study medieval and modern languages, though his focus soon shifted to entertainment and showbusiness after he joined the school's famed drama club and comedy troupe known as the Cambridge Footlights, which he eventually became the president of.

Following his time at Cambridge, where he made several lifelong friends among his comedic contemporaries, Slattery began touring clubs throughout the U.K. with a variety show until he began to appear in various stage productions and TV shows.

He finally became something of a household name when he landed the "Whose Line Is It Anyway?" gig in 1988 on Channel 4, and he was a regular member of the cast on the hugely popular program until 1995.

That show, which has since been copied for American TV, featured a slate of comedians who would perform a series of short but often hilarious improvisational comedic sketches based solely on brief and sometimes vague instructions or suggestions provided by the host or members of the audience.

A versatile actor with dozens of credited appearances

To be sure, though he is best known for his repeat appearances on "Whose Line," Slattery had quite a resume as an actor who could play both comedic and dramatic roles, according to his IMDb page.

In all, he had 49 actor credits to his name, including films like "The Crying Game" and "Peter's Friends," as well as dozens of other popular TV shows between 1983 and 2009. Slattery was also credited with more than 60 appearances as himself as either a guest or host on a variety of game shows and talk shows from 1982 until 2024.

The BBC report noted that Slattery's ability to make people laugh helped mask serious personal problems he endured for years in terms of alcohol and drug addiction that in turn covered up mental health issues he suffered for years until he sought treatment.

According to Deadline, Slattery had recently begun touring comedy clubs again and was hosting a conversational podcast known as "Tony Slattery’s Rambling Club." He is survived only by Hutchinson, whom he had been partnered with for more than 30 years.