Lynne Spillman has done the casting for Survivor since it started in the US in 2000, and can recall the days when audition tapes arrived in a dismal trickle. ‘In the beginning, I think we got 1,500 tapes. For Survivor 2, the show’s success launched into over 70,000 tapes.’ Spillman went from four people working for her to, on certain days, 40: ‘We couldn’t believe the truckloads of tapes FedEx brought to our offices. It looked like a commercial, where you opened the back and they all came pouring out.’

Robyn Kass, who has cast for the US version of Big Brother since 2001, can relate. For Big Brother 2, she says 2,000 to 2,500 tapes were sent in. For season six, there were over 10,000. ‘Closer to the deadline,’ says Kass, ‘the tapes start pouring in; in that last week we can get 2,000 a day.’ It takes Kass and her six-person staff two months to view them all. ‘We put every single tape in the vcr, and we break lots of VCRs along the way because they’re overused,’ she says.

A lot can change in five years, as this deluge of taped auditions proves. Since reality shows like Survivor and Big Brother have taken off, there’s been a lot of pressure on the casting directors to keep fickle viewers tuned in. Their selection processes have evolved, and ironically, although they have more applicants, it’s become trickier to find suitable cast members. People play roles during try-outs, or make the reality audition rounds simply because they’re itching to be on TV. Some casting directors have resorted to recruiting potential cast members on the streets to make sure they get the right group dynamic.

‘There are pluses and minuses casting for a hit show,’ explains Kass. ‘The plus is everybody knows the show, so a lot of the applicants know what they’re getting into. The minus is they know the show, so they know what they’re getting into.’

Since many have followed previous seasons closely, they often come into the process putting on an act. With Survivor, Spillman soon had to uncover ‘who was trying to play the part of Rudy and who was trying to be Richard,’ she says. ‘It got confusing and harder very quickly.’

To ensure she gets to see real personalities, Kass lives with 50 Brother finalists sequestered in a hotel for up to 10 days before they make it onto the show. ‘What they don’t realize is that all the extra time I spend going to the pool and having drinks with them, those are the times I’m really sniffing out if they’re giving me the goods. Because when they see me at dinner they let their guard down and think, ‘Oh, there’s no camera here, I can really tell her what’s going on.”

‘Everybody’s putting on a little act – that’s the position we start from,’ says Philip Edgar-Jones, who has done casting for Channel 4′s version of Big Brother. ‘We start hearing the same things over and over. They tell us they’ve got what they think we want, so they’ll say, ‘I’ll fight and I’ll argue,’ and all the rest of it, and we start from the position of not believing them.’

In addition to unearthing real personalities, it’s important to determine whether hopefuls are simply making the reality audition rounds. ‘The pool of potential contestants is smaller for Survivor now because we don’t want people that have been recycled through every reality show,’ says Spillman, who has also cast for The Amazing Race since it started. ‘With all the reality shows out there, you’ve got slim pickings. Even 20,000 isn’t enough for us to choose from because at least a third who apply have already either applied to or been on every other show.’ She continues, ‘With Survivor you really want to stay on top, so why would you pick another show’s rejects, or someone who’s already had the reality TV experience?’

In order to make sure she’s getting the freshest cast, Spillman says she recruits for contestants across the US. Over the past three or four Survivors, at least two people in each season have been recruited. One such character was Johnny Fairplay from season seven. ‘He never would have applied to the show,’ explains Spillman. ‘He had seen it, but he was this free spirit working in an art gallery in underground Hollywood. I found him on a bus bench at a gas station.’ Fairplay turned out to be one of the most villainous players in the series’ history – he even lied about his grandmother’s death.

Edgar-Jones used a different method to find one character for his most recent season. When the producers got down to a shortlist of 12 housemates, they realized they were missing ‘a good looking young man who wasn’t from the south of England – someone with a regional accent.’ Additional open auditions were held to find somebody for which the younger, predominantly female audience could root. ‘We found a guy who was our eventual winner on the show. He came along very late in the process. He had the right accent, he looked right, and he was a nice fellow.’

The UK version of Big Brother didn’t always have open calls, but after a lackluster fourth series, the casting process needed a drastic change – goodbye videotaped submissions. In comparison to the controversial third series, Edgar-Jones says the fourth ‘was actually a little dull.’ So Endemol UK looked for ‘bigger characters and more grabby kind of people’ via open auditions, which drew 10,000 to 12,000 hopefuls to meet a producer in person.

After casting for five seasons of Big Brother, Kass insists she still isn’t out to fill quotas. ‘The best people get on the show. I don’t go into the casting process saying, ‘I have to find the gay guy and the soccer mom.” But, as far as the male to female ratio, she admits, ‘Of course I’m not going to fill a house with 12 women and two men because you won’t have the dynamic or the show people have fallen in love with.’

And why have people been falling head over heels for the show? Surely buff bodies play a part. As Kass acknowledges, ‘It’s a network television show, and I’d be lying to you if I didn’t say I want to get at least a handful of good-looking people on there. It’s a show that lasts all summer, with people in bathing suits.’ She’s quick to add: ‘On top of that, I want real people with real jobs – relatable people. That’s just as important as getting the hot girl in the bikini.’

As a fellow Big Brother casting pioneer, Edgar-Jones notes that since class is a big issue in Britain, he looks for people from various economic groups. He says the guiding principle that leads his casting team is to get a mix of people from different backgrounds ‘who certainly wouldn’t go to the pub together or have dinner parties together.’ He also notes that the most recent series had a very large number of ethnic minorities in the house, but says it wasn’t done deliberately. ‘We judge everyone on an individual basis,’ he says. ‘You’ve got to spend 10 weeks in these people’s company as a viewer, so they’ve got to be interesting and have a bit of depth to carry you through that journey.’

Spillman reveals her casting mantra: ‘I always say, we have to stick with what we started with – the 16 most interesting people. I’ve said this from day one: it’s sex, conflict and humor, and if you can find the people who give you all three, that’s the show. No matter what age – 70 or 21 – you need people who have all of those qualities.’ A swimsuit-ready body can’t hurt, either.