McDaid made his debut in Doctor Who Magazine, after sending a sample strip to then editor Clayton Hickman.

His debut work for DWM was as writer of The First, a story where the Doctor meets Ernest Shackleton.

[1] He then teamed up with Glen Brunswick for a twelve-issue run on Jersey Gods for Image Comics.

[3][4] McDaid was the comic book artist on the multi-media project, Vandroid, along with Tommy Lee Edwards.

[5] In 2014 he illustrated a story written by Irvine Welsh which was published in IDP:2043, as part of the Edinburgh Book Festival.