There are a number of dystopian references in Weaverfish, hinting at the existence of a larger back story than what is directly depicted on screen. The fictional town in which the film is set is called Huxley Wells, combining the surnames of science fiction authors Aldous Huxley and HG Wells. The fictional location, Fountainhead Creek, is also named after Ayn Rand's "The Fountainhead". In Weaverfish, the company supplying the barrels of biological solvents is named Aquatopia.
Weaverfish was shot in 16 days. Most of the cast and crew were working full time jobs and took 2 weeks holiday to attend the shoot.
There are a number of crew cameos in the film. The gas-masked figures were regularly played by members of the crew, including Mark Maltby, Thomas Shawcroft, Ciaran Maginn, Charles Shawcroft and Trudy Pye. The gas-masked figure that strikes down Shannon in the long-grass was played by Director Harrison Wall.
The entire cast and production crew spent 16 days living in the household of Cinematographer and Hamble local Thomas Shawcroft during the making of Weaverfish.
Weaverfish was written to be shot in the location of Hamble-le-rice in Southampton, UK.