The introductory scene of the film features Shaun stumbling into the shot with the camera focused on his feet. Hes supposed to look like a zombie, but as we pan up we see that hes actually just waking up. Its a good sight gag, but it also acts as a reference to another Romero classic. More specifically, the shot takes its inspiration from the opening to Day of the Dead, where a zombie stumbles into the frame. Of course, this zombie isnt a knackered 30-something with an arrested development complex, but once you see it post-Shaun, you cant unsee it.