In the 1978 movie “Grease,” Stockard Channing’s character, Rizzo, is at a drive-in when she confides to a friend that she’s pregnant, before adding, “Hey Marty, you ain’t gonna tell nobody about this, right?”

The gossip spreads instantly, leaping from one parked car to another.

There will be little opportunity for gossip of any sort come May — or perhaps early June — when at least three of the few drive-in movies theaters that remain in Illinois tentatively plan to open for the season.

“It’s just a whole different thing. We used to allow pets. We won’t do that. We used to allow people to grill. We won’t do that,” said Michael Harroun, who has owned the Harvest Moon Twin Drive-in in Gibson City, about 120 miles south of downtown Chicago, for the past 31 years.

If Illinois’ shelter-in-place restrictions are eased — and there’s no guarantee they will be — Harroun plans to open up for business May 1, but at a greatly reduced capacity, doubling the typical amount of space between cars.

Scott Dehn, who runs the McHenry Outdoor Theater, said on the theater’s Facebook page earlier this month that he plans to open at the beginning of May too, saying he’s been working “hand-in-hand with the proper government authorities in developing a comprehensive plan and procedures guideline.”

“I want everyone to feel confident that this is the safest, most sanitary way to not just enjoy a movie during these difficult times, but to actually enjoy being outside on a beautiful spring/summer/fall night. With everything that we’ve been going through? We deserve at least that,” he wrote.

Illinois has nine drive-in theaters and about 325 operate nationwide, according to DriveInMovie.com, a website maintain by fans of outdoor theaters.

Mike Kerz, who co-owns Midway Drive-in in Dixon with his wife, Mia, said he’s tentatively planning to open in late May or early June. Like Harroun, Kerz plans to slash car capacity — from 500 to about 200, he said, adding it’s “just to give everyone additional peace of mind.”

He’s planning to show “Grease” and “Ferris Bueller’s Day Off,” among other movies.

In his 30-plus years running a drive-in theater, Harroun has witnessed all kinds of shenanigans, including children, stuffed like sardines inside the trunks of cars to avoid having to pay.

“Over the years I’ve had people write me letters. They’re sorry because when they were young they snuck in,” Harroun said. “So they send me the money. I always donate that money to charity.”

He charges $7 per adult and $6 for kids. The early movie line-up includes “Trolls World Tour,” Harroun said.

To keep customers safe, Harroun says he’ll be less tolerant of folks who don’t follow the rules.

“If I catch you out running around, you’re done,” Harroun said.

But after dark? “What you do in your car is your business. We don’t bother people in their cars,” he said.