Last year, Six Flags paid people $600 to lie in a coffin for 30 hours.

The amusement park is bringing back the challenge, but this time around it's asking couples to put their relationship to the ultimate test.

Couples or friends who can spend 30 hours in a coffin together will win $600 to split, a pair of gold season passes for the 2020 season, and a Fright Fest prize package.

The couples coffin challenge will start on Friday, September 27, at Six Flags America in Maryland.

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How deep is your love? Six feet, maybe?

For this year's Fright Fest, Six Flags America is challenging couples 18 and older to a claustrophobic test of endurance: spend 30 long hours together inside a 65-by-72-inch coffin. Those who make it through will win $600 to split, a pair of gold season passes for the 2020 season, and a Fright Fest prize package.

In addition to spending 30 straight hours alongside a friend or partner, coffin dwellers will be required to participate in extra challenges that will test their bravery.

The 30-hour couples coffin challenge will take place at Six Flags America in Bowie, Maryland

The challenge will begin at 4 p.m. on Friday, September 27, and end at 10 p.m. the next day.

The coffins won't actually be buried beneath the ground — but after lying in a box for 30 hours with the lid closed, you may begin to feel like it.

Participants can bring sleeping bags and pillows. Six Flags

The unlucky duos selected to compete are allowed to bring one friend during Fright Fest hours, but they will have to leave all smartphones, smartwatches, gaming devices, and other technology out of their temporary resting place. Smoking is also not allowed.

According to the official rules, eating, checking social media, and sending emails to update the outside world on the status of your pulse will be allowed during designated breaks, when the coffin lid will be opened and the contestants will be allowed to sit up but not leave their wooden beds. There will be six-minute restroom breaks every three hours, but any couple that leaves the coffin outside of those breaks will be disqualified.

Read more: Six Flags paid 6 people $300 to lie down in a coffin for 30 hours — here's what it was like

Six Flags America warns that participants "will potentially be exposed to fog, dramatic lighting, flash photography and extreme weather conditions" and that the rules may be altered for their safety.

The couples element is a new addition to the challenge

Six people took on the 30-hour coffin challenge last year. Six Flags St. Louis/Facebook At Six Flags' first 30-Hour Coffin Challenge in St. Louis last year, all the contestants won, but it wasn't easy. They had to deal with cold weather and had to sprint to the bathrooms to be able to make it back in the six-minute time limit.

They also had to lie in the coffins with the lids open the whole time, which came with its own challenges.

"The open top was brutal," a contestant named Brian Johnson said on Facebook. "Lights everywhere, people talking, you could barely sleep."

So how will it be in a closed coffin with another body next to you? Registration ends on Friday at 11:59 p.m. ET, so hurry over to the Six Flags America contest page if you want to find out firsthand.