<P> While series one and two of Black Mirror were shown on Channel 4 in the UK, in September 2015 Netflix commissioned the series for 12 episodes, and in March 2016 it outbid Channel 4 for the rights to distributing the third series, with a bid of $40 million . The 12 episode order was divided into two series of six episodes each . </P> <P> "Metalhead" is the shortest episode of Black Mirror, with a length of 41 minutes . It was filmed in black and white, a decision made by the director David Slade to bring to mind old horror films and to match the "oppressive nature" of the episode . Slade felt that the story presented a world devoid of hope, and filming "a world drained of color felt right". Brooker came up with the episode's central idea by watching videos of Boston Dynamics' robotics products such as BigDog . He found that there was something "creepy" in how the products, if knocked over, would look helpless as they worked to regain their stance . Brooker originally wanted the episode to be entirely free from dialogue, similar to the film All Is Lost . While Brooker's original script featured a human operating the dog from their home, the intention became for the episode to tell "a very simple story" and so Brooker pared back the plot . The final scene, showing a case full of teddy bears, was intended by Slade to be the only "soft and comforting" element of the story . </P> <P> The episode was directed by David Slade, who initially received the script in June 2016 . Slade was involved in Peake's casting, and had a large amount of autonomy during filming, which Slade calls "really complicated". Filming took place over England, largely in Devon and around London . With minimal dialogue in the episode, Slade notes that scenes are divided into many brief shots, and scenes utilising green screens are difficult for the actor . Real Lidar scans were used to create the scenes shown from the dog's perspective . </P> <P> In May 2017, a Reddit post unofficially announced the names and directors of the six episodes in series 4 of Black Mirror . The first trailer for the series was released by Netflix on 25 August 2017, and contained the six episode titles . </P>

Where did the dogs in metalhead come from