 CONT: When Tooms is in the cell right at the end, we see when his  food is being brought over to him on the tray that there is a drink  and a bun, when the shot changes to the other side of the door the  drink and bun have swapped sides. When the shot changes back to the  other side of the door, the tray is now the other way around and  then when the shot goes back to the other side the whole tray has  now disappeared.