You'll need to bring a second pair of pants with you if you want to participate in the first-ever "Extra Pants Subway Ride" on Sunday. View Full Caption Facebook/Tony Zaret

It could be a face-off between the have-nots and the have-extras.

While an expected 4,000 subway riders will strip off their pants this Sunday as part of the "No Pants Subway Ride," at least two people will be putting on a second pair.

Stand-up comedian Tony Zaret and his wife will lead the first "annual Extra Pants Subway Ride," a parody of the yearly pantsless stunt launched by the New York City-based prank collective Improv Everywhere in 2002.

The Greenpoint couple plans to join "No Pants" participants at Maria Hernandez Park, one of seven meeting points dictated by the event's coordinators, at 3 p.m. and board the L train at the Jefferson Street stop. But rather than stand or sit quietly until it's time to surprise other straphangers, they'll declare their intention to mount a brief piece of street theater.

The "Extra Pants Subway Ride" Facebook event instructs attendees to — as soon as the subway car doors close — "stand up and announce, 'Ladies and gentlemen, we are now going to perform a humorous flash mob. We hope you find it entertaining!'" and then put their extra pairs of pants on.

(Pant-less riders are instructed to tell inquiring bystanders that they "forgot to wear pants," that yes, they're “a little cold," and that they have no connection to fellow pants-less riders whatsoever.)

Zaret, 38, said his satirical subway ride takes aim at all flash mobs, unexpected but rehearsed performances that he objects to because, "for the first couple of minutes, most people are just sitting there thinking, why are all these people around me being so annoying?

"What if there was an announcement before the flash mob started, that we’re going to do a flash mob, we’re going to make you rethink what is theater? And then they begin enjoying the flash mob from the moment it starts. That’s why I’m trying to do the 'Extra Pants Subway Ride' a little differently."

Should we expect a rumble between the bare-legged and the bundled-up?

Asked to comment on the rival event, Improv Everywhere and "No Pants" founder Charlie Todd told DNAinfo he thinks it's "a very funny parody."

Zaret advises "Extra Pants" ride participants to wear normal pants and bring with them "a nice pair of sweats with a wide hole on the bottom, so you can just slide them on without having to take your shoes off.

"That way," he added, "you can take them off and on again, if you start to get bored and a bunch of new people come on the train, you can say, 'Oh, you missed the street theater — look, I'm putting on my pants again,' and it won’t be, like, an elaborate process.”

The Facebook event has 18 confirmed participants so far ("so that should probably mean it will be about 3 people," Zaret said), and its creator predicts it will last a mere 15 minutes.

"After a couple of minutes, the magic will be over," said Zaret, who hosts a monthly show at the Upright Citizens' Brigade theater in the East Village. "It’s not like pants off, which is exciting for hours."