If you smoke, there’s one thing you’ll know: it’s bloody hard to quit.

Like most anti-smoking advertisers, the UK’s Department of Health has spent years trying to put smokers off cigarettes. In 2012, it took a different approach. Because although negative campaigns do work, two-thirds of smokers already want to give up. They don’t need more fear.

They need more hope.

Introducing Stoptober: the world’s first nationwide quit attempt. It was a new brand, inspired by the principles of behavioural science, built around a range of tools. It made quitting attainable, by telling smokers in a friendly, non-pressuring way that quitting for 28 days makes them 5 times as likely to succeed. It made quitting socially normal – by talking about participants. And it helped smokers commit, by focusing everyone’s efforts on a single start date and then using every channel available to help them, every step of the way.

A smoker will always try to justify their habit, and being able to say ‘that’s not real’ is an easy get out.

So with this in mind we decided from the outset that we needed to create the most realistic looking tumour possible and although CGI has its advantages, when creating an organic form it can often look fake.

That’s why we worked with special effects model makers, to create physical tumours, which we could capture in camera. We created actual size smokable cigarettes that had the different stages of growth on, as well as much larger versions on scaled up cigarettes. These larger models had air bladders within them so that the growth of the tumours could be managed and captured in camera.

We also worked closely with the worlds leading cancer specialists to ensure the tumours where as realistic as possible, going through a number of revisions to get the shape, colour and texture right.

On location, each shot was filmed first with real cigarettes and then again shot using smokable prop cigarettes. Later in a studio, we matched the angle, depth of field and lighting from the location shoot to film our larger models growing in real time. These close, large model shots were then tracked onto any close up shots we had in the edit.

In the month of October 2012, 234,132 Brits quit smoking together. That’s more than quit in January.

168,000 made it to 28 days – that’s 61% of those using some form of support. The Stoptober pack was around twice as effective as the previous (hugely successful) support pack, and around four times as effective as quitting without support.

Overall, 70% of smokers were aware of Stoptober. 1.3m visited the website; 60,000 new fans joined the 73,534 already on Facebook.

Thanks to these numbers, we estimate that Stoptober will save the NHS £18,830,580 in the first year, and £41,568,024 over three years. That means for every pound we spent on it, it pays back £2.25 in the first year, and £6.17 over three years.