It has been observed that despite Patrick Cargill being the No.2 of ‘Hammer Into Anvil,’ the voice we here during the dialogue between No.2 and the Prisoner during the opening sequence is not actually Patrick Cargill's voice, but that of Robert Rietty who performed many a voice-over in both television and film.
But if you observe the dialogue between Number 2 and the Prisoner in other opening sequences, such as ‘The Schizoid Man,’ you will have observed that the voice of No.2 isn't that of Anton Rogers, but again its the voice of Robert Rietty.
So why do some episodes have the actors own voice in the opening dialogue of the opening sequence, where other’s do not? Probably it was a question of time, oh time that was it was it? Indeed, it became more time worthy to have Robert Rietty record a voice-over with Patrick McGoohan, and then use that for the majority of opening sequences.
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