You know something special is happening in a theatre when the audience start to respond to a play with gasps of horror, howls of laughter and, as in the case of Clybourne Park, cries of protest too. And smack in the middle of all this excitement was Sarah Goldberg.
"It was like being in a sports stadium. The audience was so raucous," recalls Goldberg of the play's run at the Royal Court before moving to the West End's Wyndham's Theatre. "People's reactions were so extreme, ranging from gasps, to screams, to heckles. "We were all stunned. We all came off shaking."
The 25-year-old Canadian first arrived in London seven years ago in the hope of carving out an acting career. Now she has two major roles in Bruce Norris's award-winning comic drama, a politically incorrect examination of modern attitudes towards race.
In the play's first half, set in 1959, she plays the dutiful, meek, Betsy, the deaf and heavily pregnant wife of Karl (Stephen Campbell Moore). He is the kind of old-school, white, suburban bigot most of us like to think died out with the Black and White Minstrel Show.
(And maybe they did. But the brilliance of Norris's play is in revealing that we have not moved on from Karl's attitudes as much as we like to think. If anything, Clybourne Park is a reality check for those who think "prejudiced" is a description of other people. It is also brilliantly funny.)
After the interval, Goldberg plays Lindsay, a modern-day white American who, with her partner Steve is buying a house in a black area of Chicago.
"It was so thrilling," she says of the Royal Court run. "The audience reactions were so varied. After the show people come up to talk to us in the bar to tell us their experiences with racial issues or prejudice."
Thankfully, she had no experience of her own to relate during these post-show chats. Sure, since she moved to the UK there have been the occasional anti-US comments from people who mistake her Canadian accent for an American twang. And there have been moments when things have been said in her presence that she reckons would probably not have been said had it been known that she was Jewish. But it has all been pretty mild stuff compared to the comments exchanged between Norris's characters.
"I feel lucky," says Goldberg. "I grew up in an open minded, multi-cultural community in West Vancouver in Canada. There were people who had escaped some kind of oppression. Some of them were first generation immigrants, others were one or two generations back…" (Here she may be thinking of her Polish grandparents who survived the Holocaust before moving to Canada) "…but it was a place where differences were celebrated. There weren't many Jews in my school but people wanted to know about Chanucah."
In an effort to come to terms with the bruising language in Norris's play, the multi-racial cast found themselves being comically racist to each other during rehearsals. "I'd get on Bruce's case about there not being enough antisemitic comments in the play" laughs Goldberg, before adding with mock indignation, "I have been marginalised. There is nowhere near as much antisemitic stuff as anti-black, or stuff that's offensive to deaf people."
The actress has appeared in high profile plays before, including Six Degrees of Separation at Kevin Spacey's Old Vic. But this is the most conspicuous by far.
But none of it would have happened had she not, early in her time in the UK, undergone a life-changing experience outside a famous London landmark. "I remember sitting in front of the British Museum and having a moment - an epiphany I guess - that I just had to live here. And now that I have grown to understand the British sense of humour here, I love the culture too."