The brief will be set on the night, with contenders being asked to dispense with meetings and computers and instead rely on their "pure creativity at its rawest", according to Wanda Goldwag, chair of the DMA Awards organising committee.
Goldwag said: "Forget labouring for weeks over finely crafted submissions, this DMA award is about getting it right on the night."
The award will also be judged on the night, with those taking part making a donation to marketing and advertising support charity Nabs.
The remaining 29 categories were judged last month over a four-day period.
Those on the shortlist include Harrison Troughton Wunderman, which has been nominated for a campaign for Microsoft in the IT/telecommunications category.
Others up for awards include Ogilvy One Worldwide, EHS Brann, RMG Connect and Geronimo.
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