IT WAS Friday June 24. "Black Friday." Many were still struggling to swallow the EU referendum news, and comedian Nish Kumar was playing a gig at London’s Comedy Store. More than a decade into his comedy career, it was the night he got his first racist heckle. “Go home!”, shouted someone halfway up the room. “I am home . . .?”, Kumar offered back. Born and raised in the UK, Kumar’s parents are from Kerala, India, hence his brown skin.

Fellow stand-up Paul Tonkinson was quick to Tweet about Kumar’s heckler, saying, “There’s no way this would have happened pre-Brexit.” The National Police Chiefs’ Council reported an alarming 57% rise in reports of hate crime that weekend, and hearing that xenophobes were now straying into the traditionally pretty liberal, arts-loving environs of the metropolitan comedy club sent ripples throughout certain pockets of the comedy scene. In particular, the non-white pockets.

Birmingham-born comedian Shazia Mirza has been performing material about Islamophobia since 2000, including gags about her Pakistani Muslim parents, so should be pretty unfazed about putting a non-white voice onstage by now. Yet since Brexit, she’s turned down six venues on her UK tour.

“I decided not to play certain venues, where I think it might not be safe now,” says Mirzia. “I don’t want to go to Sunderland, or Folkestone, where they’re not necessarily going to want to hear what I have to say. I wouldn’t have said that before.”

Three days after Brexit, a friend of Mirza was assaulted in the street during Ramadan, and asked, “Why haven’t you left yet?” When she replied that she was born in Britain, they spat back, “Change your f***ing clothes then.”

For Mirza, it’s a worrying jolt back to the 1970s, the last time she remembers people being openly racist.

“I was five when someone called by mum a ‘black bastard’ on a train, it was horrific. Lots of Irish in Birmingham were labelled as terrorists around then too. But that kind of visible racism - graffiti on walls, abuse in the street - I’ve not known it since my childhood. It seems so backwards and old-fashioned to go back there.”

Mirza believes certain racist views have been dormant for years, and the referendum has helped bring them to life. Sameena Zehra, a Brighton-based comedian who grew up in Kashmir, agrees.

“The referendum has unleashed something, or legitimised a lot of people’s views. It’s as if all the work against xenophobia before now, we didn’t teach them it was wrong to think like that; we just told them it was taboo. Now there’s this institutional endorsement of how they feel, certain people have just gone apeshit.”

Zehra, who will host a nightly club during the Fringe, The Cult of Comedy, and perform her solo show Poetry Can Fuck Off at The Stand, isn’t scared to go onstage, in fact it’s made her more determined to address racism through her work.

“The court jester used to make fun of society’s issues, and treat very dark matters very lightly. He could move across the entire continuum, play in front of noblemen and commoners and get away with making jokes about them all. As comedians, we need to focus on that power.”

She believes comedians are uniquely placed to speak about issues too often minimised and swept aside.

“I’m a brown, able bodied, heteronormative, middle class woman, but ask the LGBT or disabled community, and many would say the same, very disturbing problems can be written off as ‘just anecdotal evidence’ when it’s a much larger, culturally ingrained problem. It’s great these fictions are now being exposed, and we need to learn how to have nuanced conversations about them.”

Comedian Njambi McGrath has lived in London for over twenty years, and grew up in Kenya. She is writing a memoir about her childhood, where she witnessed the effects of structural racism, after both her parents were sent to concentration camps, on Winston Churchill’s orders.

“After centuries of portrayals of black people as backwards and dangerous, and these constant, subliminal messages, bigotry becomes a disease.”

Although McGrath has never experienced racist abuse in a comedy club, she admits she’s now “very nervous” about performing. If one did show up, she isn’t confident they’d want to discuss their views if challenged.

“Often it’s not a grown up debate. I would argue until I’m blue in the face, but would they want to listen? I grew up in Africa, so I know how easy it is for politicians to make people turn on one another. When people are living unhappy lives, they are very easy to incite.”

She is looking forward to playing Edinburgh, which she considers “an intelligent audience”, but is worried about other places. She describes a recent gig in Lichfield where she went on after three white male standups.

“The audience was in bits. Hysterics! I thought they’d be an easy crowd and I was about to shred it. But they just stared at me. I absolutely died onstage. I don’t want to cry racism - I wouldn’t cut it in this game if I couldn’t accept a crowd just not finding me funny. But sometimes racist vibes can be much more subtle.”

Mixed bill lineups can be more daunting than a solo show, admits Tez Ilyas, performing Made in Britain at the Pleasance.

“I’m feeling good about Edinburgh,” says Ilyas, after coming off stage at Latitude Festival. “I’d be surprised to get heckled by someone who’s seen my name and face on a poster and paid to see me. Playing to crowds who don’t know you is tougher. I’m certainly more apprehensive about playing gigs outside of metropolitan, liberal bubbles like the Edinburgh and London scene.”

For Nish Kumar, the “Go home” heckle has given him fresh material for his Edinburgh show.

“I’m 30 years old - I’m too old to be bullied! I refuse to be intimidated by the actions of a small bunch of dickheads.” He thinks of Edinburgh audiences as “judiciously comedy savvy and well behaved” and remembers a recent gig at The Stand where a drunk woman in the crowd kicked herself out before the show began, worried she was about to get boisterous.

“I’m painfully aware that I’m in a privileged, luxurious position. My job gives me a platform to discuss these disturbing ideas. In a protected environment, with security. Others don’t have that ability to challenge the idiocy. The worst thing we can do is dismiss what’s happening, and downplay the significance of hate crimes.”

Nish Kumar: Actions Speak Louder Than Words, Unless You Shout The Words Real Loud, Pleasance Courtyard, August 3-28; Shazia Mirza, The Stand, August 4-13; Sameena Zehra: Poetry Can F*ck Off, The Stand, August 4-28 (not 15); Njambi McGrath: 1 Last Dance With My Father, Laughing Horse @ Espionage, August 3-27(not 8, 15, 22); Tez Ilyas: Made in Britain, Pleasance Courtyard, August 3-28(not 15). edfringe.com