Taken in 1917, the Cottingley fairy photos showed frolicking Fairies. The creators sounded so convincing that, despite all the experts declaring the pictures as "fake", many people believed them. When the girls were old ladies, they admitted that the fairies weren't real after all: they were actually just painted cardboard. (PROSE: Iceberg)
Gwen Cooper did a school project on the photos as a child. Sir Arthur Conan Doyle and Harry Houdini believed that they were real. One of these photos showed Jasmine Pierce, a formerly human Chosen One from the 21st century, now transformed into a Fairy herself. (TV: Small Worlds)
Behind the scenes
In reality, Sir Arthur Conan Doyle did believe in the authenticity of the photos, having accepted the existence of the supernatural by that time in his life.
One of the fairies in the photo shown in extreme close-up in Small Worlds and on the Torchwood website was retouched to make it appear to have Jasmine's face.
Soon after playing the Eighth Doctor in Doctor Who, Paul McGann starred in the 1997 film FairyTale: A True Story, another fictionalised account of the photos which portrayed them as genuine.