The 60-second execution is by Abbott Mead Vickers BBDO, which has dropped the endline: "Believe."
It represents a move by the Diageo-owned brand to appeal to drinkers under 35, who account for 50 per cent of Guinness sales.
"Moth", which was filmed in the Brazilian rainforest, opens on three people in a taxi who are lost in the forest.
They are distracted by a moth flying erratically against the window, and follow it. Soon the air is filled with thousands of the creatures, resembling the swirl on the head of a pint of Guinness.
The trio is led by the moths to a lively, brightly lit bar nestling in a clearing. The ad cuts to the endline: "Out of darkness comes light."
The spot, which was directed by Academy's Walter Stern, uses the soundtrack Sing, Sing, Sing from the 90s film Swing Kids. The commercial was written by Nick Worthington with art direction by Paul Brazier.
Breaking this week, the spot will run throughout 2004, with the next execution in the series scheduled for release in September.
It will be focused on primetime shows on terrestrial and satellite stations with a programme schedule that includes Faking It and ITV's Champions League football. Media planning and buying is through Carat.
The marketing director for Guinness at Diageo, Nick Robinson, said: "This is a compelling new ad that has all the visual drama and power that you expect to be associated with Guinness.
"We feel the ad is the start of a campaign that will mark a new chapter in the heritage of Guinness advertising."