Sandra Bullock quit her job about three years ago, which is quite something if you consider that she was probably the most successful actress on the planet at the time.
It was mid-2010. Bullock, then 45, had just won her first Oscar for playing a big-hearted football mum in the tearjerker The Blind Side. A few months later, she was named the highest-paid actress in Hollywood by Forbes magazine, with more than US$56 million banked in from June 2009 to June 2010.
No one would blame her, though, for her decision to withdraw from the public eye - shortly after the Oscar came the very public collapse of her marriage to motorcycle maven Jesse James.
As multiple women came forward to spill the beans on the 41-year-old television host's extramarital activities, Bullock realised she would have to divorce him and raise Louis, the baby boy she had secretly adopted earlier that year, alone.
But a few projects have managed to lure her from her hiatus, including the newly released space thriller Gravity, which opens in Singapore tomorrow.
Bullock has top billing in the film, where she plays Dr Ryan Stone, a Nasa medical engineer on her maiden spacewalk with veteran astronaut Matt Kowalski (George Clooney) when disaster strikes and they become untethered from the shuttle.
The US$100-million (S$125-million) movie has wowed critics and audiences in North America, where it earned US$55.6 million when it debuted last week, making it the most successful October opening of all time in the United States.
There is already talk of another Oscar nomination for the versatile actress who, if nothing else, will certainly reclaim her crown as queen of the box office.
Bullock's two-decade career and 30-odd films - from her breakout action role in Speed (1994) to dramas including the Oscar-winning Crash (2004) and her trademark comedies such as Miss Congeniality (2000) and The Proposal (2009) - have amassed an astonishing US$3.5 billion in ticket stubs.
So it is understandable that there has been quite the buzz about Gravity which, together with this year's box-office-topping comedy The Heat, is viewed as signalling her big comeback this year.
In all the excitement, however, the actress has been characteristically calm and understated about the significance of it all.
At a press conference in Los Angeles, the 49-year-old is a serene, almost austere presence as she sits facing a gaggle of reporters, largely unsmiling and with eyes downcast for the duration of the session.
She indirectly references her break from acting when she reveals how Mexican director Alfonso Cuaron, whom she had been a fan of since films such as the indie coming-of-age-tale Y Tu Mama Tambien (2001) and science-fiction drama Children Of Men (2006), had wooed her out of semiretirement.
Cuaron closed the deal by travelling to Bullock's bolthole in Austin, Texas, where she has lived a quiet life, far from the glare of Hollywood, for the last couple of years.
There, he managed to persuade her to do what has been only her third film since The Blind Side, a drama about a white family taking in a poor black teenager and helping him become a football star.
"I had been such an extreme admirer of Alfonso's body of work," says Bullock, who also appeared in the 9/11-themed drama Extremely Loud & Incredibly Close (2011).
"I always use his films as examples to people to say, 'This is what we should aspire to.'
"The joke in my office every time we had a script was, 'Do you think Alfonso will direct it?' We knew the answer was no, because he makes only his own material. But then it came up that he had this project and it was at a time when I had no intention of working.
"And he said, 'Well, I'll come to Austin', and I went, 'What, Alfonso Cuaron will come to Austin?' And he did. And the conversation that we had had nothing to do with how to make the film, it had to do with the emotional core of what he felt the film was about.
"I was able to relate what I felt I wanted it to be about and our views turned out to be the exact same thing, which was mind-blowing."
Bullock has since commented that saying yes to Gravity turned out to be "the best life decision I think I ever made".
The gruelling production process, however, was a different story.
Although Clooney is a big star, this is clearly Bullock's film and the actress had the lion's share of scenes.
She filmed many of these on her own, locked in a box and hanging in the dark for hours while connected to the various cruel and unusual contraptions that Cuaron and his crew had constructed to simulate weightlessness.
Some sequences had taken years to prepare and were choreographed down to the millimetre, with a small margin of error for the actors' movements on the day.
So even when she got to work with Clooney, her 52-year-old co-star and a notorious jokester, "there was nothing fun about making this film".
"Even when George and I were together in whatever contraption we were tied into and struggling with the technology, 'fun' is not the word I would use."
The actors found comic relief only when mimicking the director's accent as they commiserated over his demanding instructions.
"Out of anger and frustration towards Alfonso for putting us there, George and I felt the need to make fun of his accent. 'Sandy?' 'Yes, George?'" says Bullock in her best Mexican accent, which Cuaron goodnaturedly tells her she "sucks at".
She says she would forget the cameras were still on her between takes and would roll her eyes whenever Cuaron uttered her name.
"Because that 'Sandy?' meant we had to do it all again. Because your nose might have gone a quarter of an inch too far forward and gone out of the screen," she says wryly.
She also filmed underwater shots where she could not exhale ("Sandy, less bubbles," the director would say) and one excruciating scene where she had to summon up all her abdominal strength to help create the illusion of microgravity.
When they finally nailed it, which takes place at a pivotal moment for her character, Bullock was so relieved and elated that she cried.
"I had to be in top core strength because I had to collapse myself while balancing on this bicycle seat.'"
At the same time, "it was so emotional".
You would not know it to look at Bullock's face, which is as impassive as ever as she says this.
But the mask flickers when she is asked if the movie, which Cuaron intended as a metaphor for overcoming adversity and an emotional rebirth after a devastating personal loss, is the rebirth of her career too.
"There's the work and there's the career. I can't control the career aspect - it's all about timing and other things, like what's available, material-wise.
"For me, it was a rebirth in my excitement in film-making and my part in it," she says.
Cuaron's inclusive approach was the reason for this, she explains.
"He's one of the most collaborative people I've ever worked with and he didn't have to be. So it was a rebirth in my faith in why I chose this profession."
But Bullock, whose schedule now revolves around son Louis, three, adds cautiously that this "doesn't make me go out and say, 'I need to do more.'
"Because I had such an amazing time on this, I've had amazing longevity as an actor and I'm just grateful for it."