"It was when Ken said something about managing an election that it all got very out of hand" said Jenny Green of the Jones Party. Meanwhile, fresh from his appearance in the Up the Polls and Round the Horne revival at the Duke of Yorks Theatre, Brian Paddick, also in the lift, averted his eyes.
And that's when the two mayoral candidates, known to be close friends in real life, took things into their own hands.
"The lift was going down, and it sounded like so was Boris" said Paddick. "We couldn't look. Meanwhile, both men were using very unmayoral language."
"Later, they appeared on the radio and pretended they were sworn enemies", said Green. "But that was just for show."
Both candidates later declined to comment. A spokesman for Johnson said the allegations were "f*ckin lies". Asked whether he supported Johnson after the alleged events in the lift, David Cameron said "f*ck off. And by the way, I'm a Christian, as it's Easter"