I have seen this exact scenario on two occasions, albeit not in class D airspace. The first was in Cornwall where the pilot got lost and confused as he entered fog. He decided to climb for terrain avoidance and call Culdrose. He was running out of fuel and had his wife and newborn baby were onboard (Yes this is true). To cut a long story short he was given vectors and descent instructions and carried out a PAR for the first time in weather conditions that would have put anyone to the test. On finals, he took out a couple of the approach lights but landed safely with only enough fuel to taxi off the runway. Needless to say, his wife wasn't that impressed and caught the train home. The second time was near Inverness where a pilot took up a group of passengers on a look around the local area, again he got caught out and went IMC without any form of instrument rating. In this instance, he tried to remain VMC below and started to get very close to the lumps and bumps. Finally, he climbed and between Lossiemouth and Inverness ATC, he was given instructions to descend over the sea until VMC, at which point he made a dash for the airport and landed. His passengers were up in arms, and the incident was reported to the police. He was eventually tried and found guilty of some offence, other than being stupid, that involved private hire and qualifications, as far as I can remember. If you find yourself in such a position, declare a PAN (yes they may take the mick out of you in the bar but at least you will be there to hear them) you will be treated with priority. If you are in the same situation as the bloke in Cornwall, upgrade the emergency to a MAYDAY. If your already speaking to ATC use that frequency if your not call on guard. I don’t know a single air traffic controller that wouldn’t do his utmost to help you out. Equally, I don’t know one that wouldn’t dine out on the story of ATC heroism for years to come.