Created by M&C Saatchi, the television and print ads will show C-3PO, played again by actor Anthony Daniels, and R2-D2 landing in a megastore car park at night. They then break in to the store and play with the products.
The three-week TV campaign will kick off on Saturday (23 October) with a 60-second ad during 'The X Factor' on ITV1. Media planning and buying is by Walker Media.
The multimillion pound campaign introduces the strapline "Discover the greatest electrical store in our galaxy".
Niall O'Keefe, UK marketing director for Dixons Retail, said: "Our Megastores offer the largest selection of electricals in the UK, and we wanted to create a partnership that would truly represent the size and scale of the shopping experience a Megastore delivers.
"Who better than C-3PO and R2-D2, arguably two of the most well-known characters in film history, to showcase exactly how vast our Megastores really are – we believe they are unrivalled throughout the galaxy."
Dixons Retail has opened 20 Megastores, which offer a 2in1 combination of its Currys and PC World chains, with the 21st set to open next month.
It faces competition from US retailer Best Buy, which opened its first stores in the UK this year, and Comet, which in September launched a new campaign based around the strapline "Come and play".