Helen Jensen can still picture the bottle of Tylenol perched in the medicine cabinet. She feels the receipt she pulled from the wastebasket. She hears the pills she poured onto the kitchen table.

And she recalls the absolute certainty, even before she finished counting, that pills from the bottle in her hand killed the 27-year-old man who lived there, as well as two of his relatives.

"Six capsules were missing, and there were three people dead," she recalled thinking.

It has been exactly 25 years since Jensen, then a nurse for the Chicago suburb of Arlington Heights who accompanied investigators to the home, played her role in a story that sent shock waves all over the country.

In a space of three days beginning Sept. 29, 1982, seven people who took cyanide-laced Tylenol in Chicago and four suburbs died. That triggered a national scare that prompted an untold number of people to throw medicine away and stores nationwide to pull Tylenol from their shelves.

If the scare has faded from memory, pushed aside by terrorist attacks and natural disasters, reminders of what happened are as close as the drug store and the corner market.

"Every time you open a bottle or package (of medicine, food or drink) that has tamper evidence features, a band around the lid or an interior seal, it is because of the Tylenol case," said Pan Demetrakakes, executive editor of Food & Drug Packaging magazine.

Jeffrey Leebaw, a spokesman for Tylenol maker Johnson & Johnson of New Brunswick, N.J., declined to comment Friday.

For those who lost loved ones or investigated the case, pain, anger and frustration remain. Part of the reason is that nobody was ever charged, much less convicted of the crime.

"It's hard to bring this up," said Patricia Kellerman, whose 12-year-old granddaughter, Mary Kellerman, died in her home after taking Tylenol for a sore throat. "Nothing ever changes," she said, her voice breaking with emotion, unable to say any more.

"I will never get past this because this guy is out there, living his life, however miserable it might be," said Michelle Rosen, who was 8 when her mother, Mary Reiner, collapsed in front of her after taking Tylenol for post-labor pains.

Rosen, 33, said she can't get the sound of her mother's labored breathing out of her head. She still sees her shaking and then falling to the floor, and her father's orders to go upstairs and take the dog. And she still hears the sound of the ambulance as it approached her house, the voices of the paramedics and the sight of her mother leaving the house for the last time on a stretcher.

"I don't remember another day in that house. I truly don't remember the funeral, (but) that day is as clear as heck to me," she said.

Police who tried to find the killer or killers say the whole episode remains part of their lives.

The case remains open, as do all unsolved homicides, though it's been years since anyone has even called with a tip, said Kenneth Galinski, the detective commander of the Arlington Heights Police Department.

The case isn't discussed much around the department, in large part because many of those involved have long since retired, Galinski said.

But those who do remember the case are frustrated — a frustration expressed from time to time, particularly from those retired detectives, he said. He acknowledges the only thing he can hope for is a confession.

"Once you get involved, it's something you never let go," he said. "You always hope you get that one phone call."

The killings marked a turning point for Jensen, 70, now an Arlington Heights trustee.

"That was an act of terrorism," she said. "I didn't even realize those words until 9/11. (But) that's what happened."