The client, developer Dragon International, has asked the firm to design a centrepiece for the 130 ha complex, which is to house film and recording studios and workshops.
The studios are to be part of a larger development, to be located on the M4 five miles to the east of Bridgend, and which used to be the site of the largest opencast mines in Europe.
Andrew German, a partner in Sheppard Robson, is handling the scheme. He said the client was looking for an eye-catching building to anchor the site.
"Dragon wants the design to have a real wow factor. It's intended to be a mini-Pinewood."
Dragon International has been working with Welsh architect Holder Mathias for three years, and together they have drawn up a masterplan for the area.
Holder Mathias is working on resolving outstanding planning issues with Rhondda Cynon Taf council and on negotiating section 106 agreements, which could include the construction of a turn-off from the M4 into the development.
Dragon wants the design to have a real wow factor. It’ll be a mini-Pinewood
Andrew German, partner, Sheppard Robson
Holder Mathias has also been entrusted with the design of a number of "silent stages", used for filming without sound, about 700 m away from the main studio area.
As well as the Holder Mathias masterplan, the vast valley area – estimated at more than the size of 50 football pitches – is earmarked for further development, with housing, a hospital and an amusement park being future possibilities.
Valleywood is being championed by Lord Attenborough, the Oscar-winning director, who will be unveiling images of the scheme at the Cannes Film Festival in May.
Attenborough said: "This is a manifestation of our own faith in the expansion of film and television production throughout the UK."
The Valleywood scheme was announced in 2002, since when it has been dogged by rumours that it might move from Llanilid to a former factory site in Newport.
The project could be in line for up to £7m of public funding through regional selective assistance – a direct grant offered to job-creation schemes – from the Welsh assembly.