The preservation of your identity could become a major concern. In many situations, you need to claim an identity and this claim needs to be verified somehow. The technology called biometrics may help. But, what if a deliberate impostor claims your identity? Will this forgery be always detected? Biometric identity verification is imperfect. This paper reviews some of the techniques that a deliberate impostor could use to defeat a biometric verification system. It focuses on audio-visual forgeries using voice conversion and face animation. It also describes identity disguise as a means of falsifying and concealing one's identity. The recovery of an identity and cancellable biometrics are also useful techniques to protect from identity theft. Such techniques could also find useful applications in multimedia.