For those who are now two sheets to the wind after all the waiting and tension, and still thinking of alternative endings so the curtains don't close on this thread yet:
The tradesperson and the mystery woman visitor turn out to be a heavily-disguised Holly and Phil, who needed a secret location to improve their skill at sneaking past cameras and pretending they're there for legitimate work purposes.
The whole thing is sponsored by This Morning, who as we speak are busy splicing highlights from this footage into a hard-hitting documentary exploring a little-known condition, Post Queue Stress Disorder that can affect people who spent too long in The Queue - namely forgetting how to live indoors again, eating straight out of the fridge, using the toilet with the door open, and continuing to sleep outside on a blanket because beds now seem 'too soft'.
The OP is actually Piers Morgan, who joined in for just a fraction of his normal fee, as getting the tabloids all whipped up, having hundreds of people hanging on his every word and toying with the public perception of TV personalities is his favourite way to pass a slow celebrity-news-week... He even found the time to indulge in his second-favourite activity: disappearing off for a while when he is in most demand, building a marble run scale replica of Buckingham Palace, and entertaining himself by designating each marble as a different member of the royal family and and playing God with their fates.
When this documentary airs next week, This Morning will take out full page ads in all the papers to make it clear that the nation's favourite duo started researching this story last Friday, at great risk to their own health, and now not only deserve awards for bravery, but full apologies from all their fellow journalists and other doubters.
Huw Edwards won't be having any of it, but as he's catching up on sleep for the next month after presenting the BBC News for ~2 weeks straight without a single toilet break, it will be a while until we hear his thoughts on the matter...