It had taken Gordon a long time to realise the voices were in his head, and not part of some public address system. At first it had been the Tube trains.
"The next station is Old Street. Change at Old Street for Moorfields Eye Hospital."
"This is Canary Wharf. Change here for Docklands Light Railway. This train terminates at Canning Town"
"Stand clear of the doors"
Then it was the buses. He'd assumed this was part of some TfL technology upgrade.
"172 to Brockley Rise"
"Newling Estate. Change here for London Overground Services"
It was all slightly irritating, but Gordon rationalised it. "Probably for the benefit of blind people", he thought to himself, "And tourists."
But eventually things began to get a bit odd. He'd first noticed it when he was cycling along Clerkenwell Road.
"This is the Fryers Delight. Change here for fish and chips."
"Farringdon Road. No right turn."
Before long he'd get an announcement every time he entered the newsagent, alerting him to the presence of newspapers and pints of milk. After spending a few days glancing furiously around for hidden loudspeakers, he'd come to the conclusion that he needed serious medical help. Thankfully, while not too keen on the Doctor's surgery and sitting around in a waiting room with people who smelled slightly of wee, Gordon wasn't the type to avoid the Doc altogether. If there was something wrong (and voices in your head saying "Next stop the sandwich shop" definitely counted as "something wrong") he would head, trepidatiously, to the surgery.
The Doctor was sanguine. "Probably nothing to worry about." He didn't prescribe anything. "Just so long as the voices don't tell you anything ... upsetting."
Gordon was slightly confused. "Upsetting?"
"Violent, I should say. I mean, voices in your head telling you to 'Alight here for Buckingham Palace' are one thing. Voices telling you to kill everyone are quite another thing"
Gordon was relived. "Oh, they never say anything like that."
"Well", said the Doctor, "I wouldn't worry too much about it then."