Charlie the badger was a hand puppet given as a Christmas gift by Charlie McDonnell, a guest presenter of special web-based episodes of Doctor Who Confidential to Matt Smith. Smith was genuinely enamoured of the gift, and tried to create a character with it immediately upon receiving it. (CON: Charlie McDonnell - Christmas Presents (badger)) It was later revealed that Smith had in fact received the puppet while filming The Rebel Flesh. Bitter cold conditions during location filming required the cast to find ways of amusing themselves. One of Smith's methods of choice was to continue to develop the voice of the badger, and to use it to amuse at least Karen Gillan. (CON: Double Trouble)
Matt Smith performing with Charlie