He is credited with co-creating the first sitcom in British Sign Language, called Small World, along with Ace Mahbaz.[4][5] The comedy series features Visual Vernacular, and relies on physical humour, facial expressions and in-jokes to bring comedy that is effective for a Deaf audience. They created the series directly in Sign Language, filming lines directly in Sign Language rather than writing the script down, and developed the series further with a series of workshops with the actors.[citation needed] He has appeared on short videos.
Duffy is an advocate for Deaf persons and Deaf culture. He has endorsed the creation of media that utilizes sign language as well as sign-presented TV, as he feels that "hearing people would understand a lot of deaf people much more if they were to see programmes like that [Small World]".[9] Of the language, Duffy has stated that "Sign language recorded on camera is exactly the same as writing on paper - it is the only way of archiving our language and culture."[10]