There was no CGI used in the short and all the effects are in camera effects.
The shampoo bottles Barry and Matt use to "help the ladies" are actually a real brand of shampoo and hair products by Umberto Giannini.
The feature length version which includes the original short within its running time was already complete when it was announced that the short had been nominated for an Oscar.
There was no budget for wardrobe so the main cast borrowed uniforms from the store and shoppers wore their own clothes.
The short film was filmed over four nights in Sainsbury's Whitechapel branch in London. The crew filmed while the store was closed from 10pm - 6am.