Cadbury's 'Eyebrows': two kids, one gesture, no dialogue, 4m views in three weeks

Cadbury Dairy Milk's 'A Glass and a Half Full' platform, run by Fallon London through a fictional in-house production company, sold chocolate as a moment of joy rather than a product claim. A gorilla drumming to Phil Collins (2007) and airport trucks drag-racing to Queen (2008) had both delivered creatively and commercially. The third original film, inside a £3.7m campaign, had to break live during the Celebrity Big Brother final on Channel 4 on 23 January 2009 and then keep travelling online. BBC News summed the brief up as getting an advert with the same impact as the infamous drumming gorilla.

Strip the ad to one involuntary gesture: two kids left alone in a photographer's studio perform a whole dance routine using only their eyebrows, no dialogue.

Fallon creative director Nils-Petter Lovgren took the idea to executive creative director Rich Flintham and wrote it up as, in his words, half a page and an image; Cadbury marketing director Lee Rolston and senior brand manager Lucy Evans bought it straight off the bat. Directed by Tom Kuntz through MJZ, the 60-second film opens on two children in Cadbury purple waiting for a school portrait. The photographer leaves to answer a phone, the boy presses a button on his watch, and Freestyle's 1986 electro track 'Don't Stop The Rock' starts. The kids perform a choreographed eyebrow routine across several cameras, cut like a music video; a pink balloon Flintham contributed lets the girl squeeze air on the beat, sounding like a needle scratching vinyl. Lovgren's method was subtraction, and casting was the hard part: finding children with eyebrows this talented. Cadbury then built participation around the gesture, renaming February 'Febrowary', polling the public for an 'eyebrow king and queen', publishing a house statistic that only 35% of Britons can move their eyebrows independently and 18% of those are fully eyebrow ambidextrous, and tying in with Photobox so people could paste comedy eyebrows onto their own photos and print them on mugs.

Cadbury said the film was viewed more than 4m times on YouTube and other video sites in its first three weeks. The Guardian counted 54 video responses on YouTube and noted amplification from Kanye West's blog, Perez Hilton and Stephen Fry. Lily Allen and Alan Carr parodied it on Channel 4's Sunday Night Project; Setanta Sports' Special 1 TV ran a version with puppet doppelgangers of Wayne Rooney and Sven-Goran Eriksson. Orange, also a Fallon client, gave the soundtrack away as a ringtone and it was downloaded 125,000 times in the first 11 days. ITV's Ad of the Decade poll, compiled by TellyAds, ranked it 19th.

By January 2009 Cadbury Dairy Milk had an awkward problem: its two previous films were among the most talked-about British advertising of the decade, so a third was expected to be worse. 'Gorilla' (2007) was a man in a suit drumming to Phil Collins; 'Airport Trucks' (2008) was lorry drivers racing to Queen. Neither explained chocolate. Client marketing director Lee Rolston told Campaign to judge creative and commercial success separately, said both earlier films had delivered on both, and named warmth of feeling as the dial to turn up.

Fallon's answer was to take almost everything away. The film Lovgren wrote runs 60 seconds with no dialogue and no product demonstration: two children sit for a school photograph, the photographer is called to a phone, and the pair perform a routine using only their eyebrows, cut on the beat by Tom Kuntz. Lovgren said what they took away, rather than added, worked better, so long as the details never overshadowed the main action. The track had to come from a narrow road between funk, disco and hip-hop; he tested it by playing it loud in the office until health and safety told him to stop.

Cadbury then made imitation part of the campaign rather than leaving it to chance. Fallon partner Chris Willingham said the work was designed to encourage involvement and imitation. A Photobox tie-on let people paste comedy eyebrows onto uploaded photos; February became 'Febrowary'; a public poll searched for an eyebrow king and queen; a follow-up called 'Jivebrow 09' invited viewers to perform the routine back. Cadbury seeded its own pseudo-research too, claiming 35% of Britons can move their eyebrows independently and 18% of that group are fully eyebrow ambidextrous.

It travelled: 4m views in three weeks by Cadbury's count, 54 YouTube responses logged by The Guardian, links from Kanye West and Stephen Fry, TV parodies from Lily Allen and Alan Carr, and 125,000 ringtone downloads in 11 days via Orange. It also divided opinion, which kept it in the conversation. BBC's Ad Breakdown ran a planner's verdict that the humour felt forced beside Gorilla, and readers argued in the comments about whether the children were funny or frightening, while admitting they could not tell if the eyebrows were real or computer-generated.

A single facial gesture costs nothing to imitate, so the audience became the distribution: offices, schools and TV panels could all perform the ad without a budget.

No dialogue and no product claim removed the two cues that make advertising skippable, so viewers judged it as a performance rather than a sales message.

Music-video grammar, several cameras and cutting on the beat, gave it a native format for YouTube in 2009, before brands had any social playbook.

Cadbury built participation scaffolding around the joke, Photobox eyebrow uploads, a Febrowary poll, a made-up ambidexterity statistic, so the press had facts to report beyond the film.

The client bought a half-page idea because smiling at it was the test; simple enough to judge in one glance meant simple enough for the public to repeat.

When your last hit was one absurd gesture, the sequel works by shrinking the gesture, not scaling it: Cadbury traded a gorilla for two eyebrows and got an audience that could perform the ad.

The routine joined Gorilla in Cadbury's canon, ranked 19th in ITV's Ad of the Decade poll compiled by TellyAds. The platform kept recycling its hits: Gorilla re-scored to Bonnie Tyler's Total Eclipse of the Heart, the Truck ad to Bon Jovi's Living on a Prayer, and Eyebrows followed by 'Jivebrow 09', asking the public to dance it back. Lovgren expected more Glass and a Half Full films with other names in the credits. The format outlasted the platform: one unexplained physical gesture, filmed deadpan and easy to copy, became a template for ads built to be imitated.