'Bryony Makes a Zombie Movie', which at 3.33pm, will follow all aspects of Matthewman's production, with coverage consisting of two webisodes each week over a 17-week period.
Content will include coverage of shoot days, potential interviews with the celebrities of the undead world, make-up testing (exploding heads), and responding to the demands of the community.
Matthewman is a YouTube heavyweight, best known for her one-woman comedy sketches impersonating celebrities such as Amy Winehouse and Britney Spears, which have collectively been viewed several million times.
She announced her idea for the documentary in a YouTube video she posted on her Paperlilies profile on Monday June 2.
A month later, Matthewman's call to arms had attracted some 140 video responses, more than 3,500 message board comments, and over 280,000 views.
Matthewman has to complete the zombie movie by Halloween 2008, when she will throw a premiere party involving as many contributors as can make it, all dressed in zombie outfits.
Throughout the web series, she will report on the weirdest, worst and most wicked suggestions, video responses and volunteers, from all over the world.
Hat Trick will also produce a 30-minute TV programme telling the full story of Matthewman's journey from initial video post to red carpet premiere.
Danny Cohen, controller of BBC Three, said: "This project is part of BBC Three's latest commitment to being a multi-platform network.
"Bryony is part of a new generation of internet talent that our young viewers are already engaging with and, for BBC Three, Bryony is someone we want to nurture."
The executive producers for Hat Trick are Jonathan Davenport and Richard Wilson. It is produced by Adam King and commissioned by Martin Trickey, multiplatform commissioning executive for comedy and entertainment at BBC Vision.