​On the morning of Valentine's Day, 2012, Alex Greenwich had a meeting in the prime minister's office. As co-chair of Australian Marriage Equality, he'd come to speak with Julia Gillard's senior advisers. (Gillard remained opposed to same-sex marriage until 2015 – two years after she was ousted from the top job.)

As talks progressed, Greenwich made an announcement: that evening, Magda Szubanski would come out, live on The Project. By doing so, she hoped to "supercharge the case for marriage equality".

Gillard's advisers exchanged furtive glances. In that moment, they realised their jobs had become even harder. "By the looks on their faces, they knew this was going to have a massive impact," Greenwich says.

In 2003, Szubanski topped the list of Australian Q-scores: a measure of celebrities' familiarity and appeal. The next year, she broke her own record. According to one agent, little has changed: "Everyone knows Magda, everyone loves Magda – and that's been the case for 25 years now."