Guy was born in suburban London in 1972, where he attended a local comprehensive. After reading English including Medieval studies at Exeter University he went into the film industry as a runner. After a year and a half he realised that running was a good way of getting nowhere fast. He made the 12 minute short film "The Typewriter" on a total budget of £12, which was enough to earn him a place at film school in Bristol.

At Bristol he met Dan Rack, who has worked on all of his subsequent films as Cameraman. The Bristol course was general, but intensive. Here Guy wrote and directed some projects and edited others. He left film school with a basic knowledge of Avid editing, which proved enough to launch him straight into being a First Assistant Editor on a feature film, such knowledge being scarce at the time. Since then he worked in that capacity and occasionally as Post-Production Supervisor on more than a dozen features, ranging from BAFTA winning art movies like "The Warrior" to Hollywood studio productions such as "Calendar Girls" giving him insight into the workings of a broad range of different styles of filmmaking.

Meanwhile Guy was making contacts and raising money to make further short films. These shorts included "Delusion" and, most recently, "Telling Mark" which has screened at international film festivals and been sold to HBO. His time spent in feature film cutting rooms paid off on these projects, allowing him to shoot with economy and confidence material that actually cuts together. This time also gave him access to established Producers and Directors who were generous with their help and advice, and sometimes even cash.

In between short film projects Guy devoted his time to the infinitely cheaper art of script-writing. Four spec feature scripts, "Breakdown", "The Book of Dreams", "The Bridge" and "Panoptes", and a prize winning short script have led to work writing on commission.