Agency Republic's remit, which is across creative and media, will include the development of an online marketing strategy and the ongoing delivery of customer traffic to the Blockbuster .
Sarah Baxter, marketing director for Blockbuster, said: "The appointment of Agency Republic is the next step towards extending our core proposition online and allows us to benefit from specialist digital media and creative expertise."
The video-rental chain announced that it was holding a pitch through the AAR in December. Blockbuster is 82% owned by Viacom, which also owns the MTV networks.
Martin Brooks, managing director of Agency Republic, said: "Blockbuster is a massive brand in the entertainment world. It's clear that the creative communications should reflect this and entertain the viewer in their own right. We're looking forward to a strong business relationship with Blockbuster".
Blockbuster's media account is currently held by Walker Media with creative through Doner Cardwell Hawkins.
Viacom had considered selling the video-rental chain but having failed to find a buyer it now looks likely to spin it off in an exchange of stock between shareholders of Viacom and shareholders of the 18% of Blockbuster already owned by the public.
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