There’s nothing a Cambridge student likes better than organised fun. Whether you’re swapping your way through your twice-weekly designated debauchery, making gun fingers to music the sixties would be ashamed of, or huddled around a fountain singing hymns in Latin, people seem to need the reassurance of a well-organised night out.

Perhaps this is why none of the blazered silhouettes huddled in the drizzly shadow of King’s College Chapel seem to think they’re doing anything out of the ordinary. It’s a Friday night and I’ve just spent an evening with the Chetwynd society, a collection of choirboys and their non-musical mascots who come together fortnightly to celebrate one of Cambridge’s oldest ongoing traditions.

And the evening is actually fairly normal. Until the stroke of midnight.

The current secretary, Robert Hawkins, a softly-spoken History of Art student, greets me with bumbling affability in the first of the two rooms turned over to the night’s festivities. Robert himself is not in the choir, although most of the members are. Anyone can attend the fortnightly gatherings provided they come armed with a bottle of wine.

With no prompting, Robert anticipates the various parts of the night I might find offensive. During the proceedings, of which I am as yet ignorant, all women are referred to as ‘Mister’ with the syllables ‘H.G’ after their name, standing for ‘honorary gentleman’. Robert spends a significant amount of time convincing me that this tradition satirises a less enlightened era when women were not allowed to be members. He continually reassures me that the society is totally open – no discrimination here, Squirrel.

The Chetwynd society was founded in the 1890s. Originally a debating society, Robert recounts how it became “progressively sillier”. After being taken over by sporting clubs who made it into more of a boozy affair, it was eventually turned over to the college choir, which was presumably when all the singing around the fountain came in.

Robert’s protective instincts reveal the deep affection that many of the members seem to hold for the club.

Also in attendance are a fair number of old members, and some, like the larger than life Andrew Morris, have been coming ever since their undergrad days. A character Richard Griffiths might once have had a good shot at playing, Morris too goes on the defensive about the club’s perceived exclusivity.

“We all have our own social circles,” he assures me, “even people in dockyards live in their own little worlds.”

“Did you ever work in a dockyard?” I ask.

Andrew Morris grips my elbow. “I’m afraid I used to work in a boys’ public school,” he says apologetically.

Midnight strikes. The rituals begin.

Andrew Morris lets go of my elbow as Robert mounts a table. Standing aloft above the waiting crowd, he is clutching a leather-bound book in which he has written “the minutes”. Presumably originally used to record the debating society’s informed conclusions, this ten-minute speech delivered by the club’s secretary has descended into an account of the various salacious things members of the society have recently got up to. I later discover that this is the first time Robert has read “the minutes,” a task about which he is understandably nervous.

“My dear Chettys,” he begins, “welcome to our 1582nd meeting.”

“That’s a huge number,” the members bellow back at him. And throughout the speech that follows, every possible innuendo is hurled back at Robert, as a room full of choral singers is transfixed by a grown man standing on a table surrounded by cheese. Andrew Morris wipes his mouth with a red spotted handkerchief whenever the rousing decontextualisation of the syllable ‘tit’ gets too much.

I later discover that Robert is fairly bashful about his innuendo-laden speech. He had written it carefully before gluing the printout into the book, even quoting Henry V at profound moments.

“That kind of got lost” he admits. “What I didn’t anticipate was how rowdy everyone would be.” A stickler for tradition, he has highlighted his intentional innuendos in bold.

I lean over and read what he’s written.

“Climax…titillate….inserted.”

“Yes, well, you get the idea,” he says, closing the book.

The minutes done, the assembled company don their coats and head downstairs. I follow them to the lawn in the middle of Front Court, as the porters flash their torches to make sure no one climbs into the fountain. Holding umbrellas over each other’s heads, one of the best choirs in the world sings the college founders’ hymn, belting out the age-old tune from throats oiled with wine.

Then, in an unexpectedly base turn of events, some of the more lash-loving choristers head away from the still-humming crowd. Orderly as an evensong service, the boys line up against the wall of neighbouring Clare college, and piss on it.

Robert later tells me he isn’t so keen on this part. But even this well-turned-out History of Art student can’t change it. He is part of a tradition older, and bigger, than himself.