The narrative for the episode revolves around the titular Smithereens, a Facebook-like social media platform designed to be highly addictive. Brooker and Executive Producer Annabel Jones approached Framestore Television to build the interface design for Smithereens and handle all the screen comp and replacement work that brought the fictitious social media app to life.​

Led by Shoot Supervisor William Bartlett, Framestore’s Smithereens team worked on 150 shots in the episode, many of which were implementing the UI and visual aesthetic of the Smithereens app on handheld screens, digital signage and the interiors of Smithereens’ head office. The team also provided set extensions, digital matte paintings and array manipulation for the episode's dramatic car crash scene.

‘We worked through a large variety of concepts for the interior walls and screens of the Smithereens headquarters,’ says Framestore’s VFX Supervisor, Owen Braekke-Carroll, ‘marrying the aesthetic of the company’s other branded elements that appear throughout the episode. This concept work informed our design for the Smithereens HQ which had to walk a fine line between being plausible and futuristic.’​