That was the cloister bell in room Eleven, right? I'm not a Classic Who watcher, and the only time I've heard that noise before was when the Master turned the TARDIS into a paradox machine. So is it the Master he's seeing ("of course it's you") or the TARDIS, wrongified (ditto)?
Also posted at
http://kouredios.dreamwidth.org/201713.html ; feel free to comment there if you so choose:
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