The 2017 Oscars will definitely be remembered for its groundbreaking lineup of talented contenders, but, unfortunately, it will also be remembered for an unprecedented mistake that gave rise to one of the most sensational scandals in the awards’ 89-year history.

It all happened when Brian Cullinan, an accountant from PwC, a London-based accounting firm that has tallied the votes for the Academy Awards for the past 83 years, mistakenly handed the wrong envelope to presenters Warren Beatty and Faye Dunaway.

As a result, “La La Land” was erroneously announced as the best picture award winner. The mistake was revealed just as the film producers wrapped up their acceptance speeches – “Moonlight” was in fact the winner.

The audience and millions of viewers around the world watched in disbelief as the bizarre scene played out on stage. In the meantime, PwC executives rushed to mitigate the unraveling PR crisis.

The company’s century-old reputation was suddenly under a very serious threat. And for a business that provides accounting, tax advisory and consulting services to some of the world’s largest corporations, a tarnished reputation could result in billions of dollars in lost revenue.

The unfavorable publicity spread on social media like wildfire. Both hashtags #Oscarfail and #Envelopegate were trending on Twitter on Monday following the event.

To its credit, PwC acted quickly, apologizing for the mistake on Sunday night and releasing a statement on Monday evening, accepting “full responsibility” for the “breaches of established protocols” that led to the monumental debacle.

“Once the error occurred, protocols for correcting it were not followed through quickly enough by Mr. Cullinan or his partner,” said the statement, referring to another PwC employee Martha Ruiz.

As part of the company’s crisis response strategy, in addition to the released statement, later that Monday, The United States chairman of PwC Tim Ryan also sent emails to company employees regarding the incident, according to The New York Times.

During force majeure events like this, a company’s financial stability and often its very existence depend on its crisis communications team. And so far, PwC’s response has been prompt and well coordinated.

From a public relations standpoint, however, it will be interesting to see how PwC will frame the brand’s narrative going forward. But for now, the firm’s coordinated crisis PR response has proven to be quite effective.