It all started with a summer barbecue, held at the agency's Berners Street offices last month.
To accommodate its guests, AIS laid down artificial turf on its roof terrace. It looked great and was well received by the guests, but, as the agency was later to find out, it came with one vital flaw - it wasn't permeable.
So after a day of rain, Ingall ventured up to the roof only to find the agency's digital guru, Jon Buckley, with his trousers pulled up to his knees, wading through a pool of water, which was threatening to seep through to the floor below.
Not a great start to the day, then, having your roof flooded, but that was by no means the end of Ingall's problems.
After leaving the roof, Ingall was on his way back down to a client meeting with O2 when he was greeted with a loud bang.
The electricity had blown and the entire building lost power - not, as first expected, because the water and electricity had mixed together to form an explosive cocktail, but because a workman outside had managed to drill straight through the agency's power cable (leaving him with no hair on his left arm).
This left the building without any electricity for the entire day, which isn't just a problem when you've got an important client meeting going on, but meant that the building's electrical front door system didn't work either, trapping both staff and clients inside.
It was a fitting end to a day that would have seemed far-fetched even if it was compiled by the writers of Fawlty Towers.