It's Tuesday evening in RTE's Studio 6, a tiny space that's about to play host to something pretty big: the first ever live advert on Irish television.
The 90-second commercial for 11850 Directory Enquiries is due to air on TV, radio and the web during half-time in the Munster vs New Zealand rugby match, and everyone involved, from broadcasters to ad men, seem eerily, suspiciously calm.
"Worst-case scenario, we'll hope for a streaker," laughs Jason Hynes, the copywriter from ad agency The Hive who is scripting the big event.
The deadline is just hours away, and Hynes will soon be locked away in the studio with Paul Reid and Feidhlim Cannon, the two actors who play the mullet-haired, mustachioed characters '118' and '50', going through some final rehearsals with a provisional script that is to be amended to reflect the action in Thomond Park once the game begins.
"I know Paul and Feidhlim a while, so we're comfortable with each other," Hynes tells me.
"It also means I can shout at them without anyone getting offended!"
The two guys themselves are out of bounds before the transmission. Watching them on a screen from the control room, I can see that they're concentrating hard on making it all look fun and breezy. The task at hand seems easy, but on live television, 90 seconds can be an eternity if anything goes wrong.
As the game kicks off, various ad heads begin chatting nervously, while they wait to clear the copy that will go on air. It seems settled by 8.10pm, but in the last few minutes of the first half, Munster surge ahead 16-10. It's hard not to smile at the surprise in the actors' voices at that news.
New jokes and soundbites are needed, and there's two minutes to get it done. Quips about the haka and the slimming effect of the colour black raise chortles in the room. It's good to go.
Save for a minor timing issue (unnoticeable to us mortals), it all goes off without a hitch. For all their earlier confidence and sense of control, the agency people and broadcast assistants visibly get some colour back in their faces straight after.
The two stars are immediately ushered out of the studio for a much-deserved beer in the green room.
"I wasn't nervous until Feidhlim said that there's a million people watching," Reid laughs. Cannon adds: "I think that's when we both thought, 'Holy sh**'."
Television viewers should get used to these kinds of advertising stunts that set out to grab our attention in unusual ways.
Modern audiences are more fragmented than ever before, thanks in large part to the huge choice of digital channels, and the increased popularity of 'time shifted' systems such as Sky Plus, which allows viewers to skip through the ads.
In addition, many younger viewers now watch their favourite shows on computers and laptops, either by file-sharing and downloading, or by streaming on websites.
For these reasons, advertising has become all about creating a sense of occasion through 'event' campaigns such as the bizarre but wildly popular Cadbury's gorilla ads, or the spectacular mini-movies by Chanel, which were helmed by Baz Luhrmann, the visionary director of Moulin Rouge, and starred Oscar-winning actress Nicole Kidman.
Live advertising is the latest stunt to keep commercials relevant and exciting in this new viewing environment. In May of this year, Honda captured the popular imagination when it staged Britain's first live TV ad. Inspired by the company's slogan 'Difficult is worth doing', the concept involved a team of sky divers leaping out of a plane somewhere over Madrid to spell out the word 'Honda' in formation.
The three-minute, 10 second advert ran for an entire ad-break on Channel 4 during an episode of Come Dine With Me and was watched by an average of 2.2 million people.
Live adverts were actually the norm on American television in the 1950s and '60s, but now the old techniques have been disinterred in an attempt to reach the modern 'time shifting' viewer. Earlier this year, late-night talk-show host Jimmy Kimmel began personally ad-libbing commercials in the middle of his show for firms like Nikon, Samsung and T-Mobile.
Since May, the ABC network which broadcasts Kimmel's show has pocketed some $4m (€3.1m) in advertising revenue from the live spots (and the slots are all filled up for the rest of the year too).
Tuesday night's live ad was a first for Irish TV, but the whole concept of live advertising, in fact, harks back to the earliest days of radio here.
RTE broadcaster Brendan Balfe, who has worked in the business for 40 years, says that there were live commercials on Irish radio from as early as the 1920s.
"The state's first radio station 2RN indicated it would broadcast 'advertising lectures' for a modest fee," Balfe explains.
"There were only a few takers, like Euthymol Toothpaste, and they were apparently scheduled after real programmes, just before closedown."
When Radio Eireann was founded, the concept of live commercials slowly evolved into sponsored programming, which allowed two 45-second commercials within a 15-minute programme, in addition to an opening and closing slogan.
"Many sponsored programmes were recorded, but there were some stalwarts that consistently went live from the Sponsored Programme Suite in the GPO, and later in the radio centre," Balfe recalls.
"Some of the main live ones were the Irish Hospital Sweepstakes Programme, with Ian Priestly Mitchell, Bart Bastable and Val Joyce (the advertising slogan was, 'Makes no difference where you are, you can wish upon a star'), and The Birds Programmes with Cecil Barror, promoting Birds Custard and Birds Jelly De Luxe."
In the 1960s, spot ads were introduced widely, such as on the popular Morning Melody record programme, which had two presenters, one for the music, and one for the commercials, which were promoted as "good bargains for housewives", and read live in five groups over the hour.
Despite technological advances, and the increased use of recorded ads, the practice lived on until more recently than one might think.
"Live commercials continued into the 1980s, if memory serves," Balfe says. "The commercial reader would visit whatever live programme was on the air and read the same commercial over and over during the day."
As for modern live TV adverts, the publicity preceding Tuesday night's 11850 promo has arguably been more rewarding for the company than the ad itself. It can only be a matter of time before other Irish firms find ways to push the live format even more. Watch this space.