Take all the ingredients in a typical drive-in movie: snacks, friends, a classic blockbuster and a weekend night in July.

Forget about the cars, though: This event is on the water.

The flotilla of watercraft that tied up Friday evening on Lake Minnetonka held boaters who weren't just there to swim and grill out. As night fell, a silver crescent of moon sparkled above the 40-foot-wide movie screen mounted on a barge at Big Island, and FM radios on boats reverberated with the sound of jet engines as "Top Gun" played on the floating screen.

The second-annual event was dreamed up by the guys at a boat dealership, who see it as a way to drum up a little business while hosting a free, family-friendly event in an area that is better known as a party spot for the younger set.

Mike Andersen and Kyle Pillsbury of MarineMax in Wayzata were brainstorming events for boaters when they came up with the idea.

"We were sitting around one night and said, 'How cool would it be to sit out on the lake and watch a movie?'" Andersen said.

Very cool, if you ask Margie Vechell, one of the several hundred boaters at Friday's movie. "It's just relaxing," said Vechell, who was bringing burgers and hotdogs for her kids and an assortment of their friends and cousins. Families tie up "boat-to-boat-to-boat," as she put it, then wander about to visit.

"We grew up boating on the lake, my family and I, and now I get to take the kids out," said Stu Francis, who brought 4-year old Isabel and 2-year-old Isaac to the movie along with apples and Gatorade.

"It's a great way to get to know other boaters," said Eileen Manning, a MarineMax customer who brought her boat out to grill burgers and make s'mores with relatives from Chicago.

Hot summer weekends can find Big Island hopping with boaters who often show up on Friday and stay until Sunday, said Lt. Kip Carver of the Hennepin County Sheriff's Water Patrol.

"I don't want to make it sound like it's some big party place, but people are definitely out there enjoying themselves," he said.

At times, things have gotten out of hand. In 2003, a man who had been drinking reportedly got into an argument with two men in another boat, then fell into the water and died. Rescue efforts were hampered by boaters who refused to move for emergency personnel.

Safety lanes have been put in since then, and Carver said most of the problems this summer have been commonplace -- medical calls about dehydration or twisted ankles, for example.

Events such as the boat-in movie are good for the area, he said, and the guys at MarineMax are glad to hear that. Still, turning their vision into reality for the first time last year "took way more than I ever thought," Andersen said.

First, there were the permits. Turned out, they needed permission from the Water Patrol and the Lake Minnetonka Conservation District.

The Water Patrol got several calls from lake residents who worried the movie would make for a noisy night. "A lot of people were concerned that it was going to be a big party on the lake, which it's not," Andersen said.

Then there was the problem of where to mount the screen. The organizers couldn't get permission to put it on shore, so they got a barge instead.

Then they had to figure out how to keep the screen from tipping over. "Typically we would put large stakes in the grass, and tethers would come down from the top to hold down the screen," said Terry Iverson, owner of Twilight Zone Outdoor Cinema Services, which helps put on the event. "But there's nowhere to do that out in the water." The solution? A crane that secures the 500-pound screen.

Inflating the screen's frame is kind of tricky on the barge. "If it were to come down in the water, I don't know if we'd be able to get it out," Iverson said.

Iverson said he always gets a little nervous before an event, but before last summer's movie, "it was too expensive and too time-consuming to do a test run," he said. "So even on the day of the event, we weren't exactly sure how well it would work."

But the weather last year was great, the screen stayed upright and about 250 boats showed up for a quiet viewing of "Ghostbusters."

"Someone was actually popping popcorn out there, and you could smell it floating across the lake," Vechell said. When the theme song played at the end of the movie, she said, "everybody was singing along."

Sarah Lemagie • 952-882-9016