Original title: Agent Cody Banks 2: Destination London (USA, 2004)
German title: Agent Cody Banks 2: Mission London (Release date: 08.07.04)

IMDB: https://dereferer.me/?https://dereferer.me/?http://www.imdb.com/title/tt0358349/combined

Amongst the gadgets Cody gets for his mission is a high-end directional microphone built into his retainer that he can control with the movement of his tongue.

Some close-up shots of the retainer while out of and in his mouth and a brief dialogue when you can hear Cody heavily lisping.

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