Please stand clear of the closing doors and remove your pants.
Almost 150 Brisbanites ditched their trousers, shorts and skirts for more than two hours on Sunday for a jaunt around the city's rail network.
The mass self dacking, starting as the Gold Coast train pulled away from Central Station just after 3pm, was billed as a "celebration of silliness" - a chance to make people laugh, smile and forget about their worries.
There was no doubt the pantless were having a good time as they read newspapers, played on their phones and otherwise mostly pretended everything was normal.
They were told to stay straight-faced and say something like "It's too hot for pants" or "they were getting uncomfortable" if anyone asked why they were sans trousers.
It wasn't always clear how those not in on the joke felt to suddenly be surrounded by commuters on the somewhat incorrectly named Brisbane No Pants Subway Ride.
For many, shocked or confused looks quickly turned to smiles but others were clearly put out by the garish underwear dotted around their carriage.
Reactions ranged from "obnoxious" and "a bit weird" through to "interesting" and "a bit of fun".
"It's a no pants train ride. We just happen to be on the wrong train," one older couple laughed.
Fun-seeking commuters old and young dressed in everything from motorbike gear and business suits to casual summer clothes, minus the bottom half of course.
One man spotted a loophole and donned a kilt for the journey around Brisbane's inner city, which wound up with a stroll walk through Fortitude Valley for a tipple or three.
The global event kicked off in New York in 2002 with seven members of the Improv Everywhere group, slowly growing year on year before expanding worldwide and reaching Brisbane for the first time in 2009.
More than 1300 people indicated on Facebook they planned to attend the 2016 edition but as expected by organisers, the real number was only about 10 per cent of that.
Brisbane improv enthusiast and organiser Adam Spencer counted 149 pants off crusaders, well up on last year.
"It's just a celebration of silliness. It's something to have fun," he said.
"People get really stressed around this time of year so it's just basically for people to relax and enjoy themselves and shock a few random passengers into a smile."
Police and Queensland Rail were tipped off in advance to help things go smoothly.
"The event has been ongoing for a number of years and Queensland Rail works closely with event organisers and the Queensland Police Service to ensure the event does not cause concern or offence to other travelling customers," a Queensland Rail spokeswoman said.
A police spokesman said there were no incidents.