Dateline gives you a behind-the-scenes look at one of the most stressful, high-stakes jobs on the planet: medical residents, new doctors getting on-the-job training at real hospitals, with real patients.

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You'll watch young doctors grow, right before your eyes. Thirty-hour days, long lonely nights. Making mistakes, and learning from them. This is where medicine and miracles first meet. NBC News chief medical editor Dr. Nancy Snyderman reports on "The Heroes of Children's Hospital" on Dateline Sunday at 7 p.m. ET, 6 p.m. CT.

Also: In this age of high-tech security, you might think it impossible to walk into one of the world's most exclusive jewelry stores and steal millions of dollars in diamonds in just a matter of seconds. But a bold band of thieves managed to do just that, over and over again, for 20years - all caught on camera. Just how did they do it? Who were these mystery men? And could they ever be stopped?

NBC's Keith Morrison goes "On The Trail of the Pink Panthers."

When it comes to solving a crime, time is the enemy. As the years pass, memories fade, the trail grows cold, life moves on. This is the story of a murder that, after seven years, might never have been solved. The victim - a new mother - had been forgotten by almost everyone - except a complete stranger determined to find justice.

NBC's Lee Cowan brings you the story of the man "Behind the Badge."

See it on Dateline Friday at 9 p.m. ET, 8 p.m. CT on NBC.

By Vince Sturla
Dateline NBC producer

Vince Sturla is the producer of Dateline NBC's "A Matter of Time." Click here to read the transcript.

When does a person die? At what specific point does the transition take place from life to death? Of course we know the precise moment when death occurs if there's been massive, instantly fatal trauma — a gunshot or car accident. But what if there's been a heart attack or a stroke? In those cases, a doctor told me, "We don't really know the exact time when a person dies." Is it when the heart stops? But there are documented cases of people who have been brought back to life after their heart has stopped and can recount events and conversations that took place when they were "dead." So does death occur 5 minutes after cardiac arrest, or 20?

It's not merely a theoretical question, as our report, "A Matter of Time," makes abundantly clear, and the stakes are particularly high when it comes to organ donation.

Most of the time, doctors procure organs from donors who have suffered "brain death," which has a clear, distinct, legal and medical definition. If a person has been declared brain dead, it's been determined there is no brain function. A death certificate is issued even if the heart and organs are being kept alive through artificial means until they can be removed and transplanted to a patient who needs them. It's strange to think that a person could be in a hospital, in a bed, connected to a ventilator but dead for hours, even days before the organs are harvested. There is nothing vague about these procurement operations. The transplant team comes in, the donor is disconnected and organs removed--all in a matter of minutes. But according to the U.S. Department of Health and Human Services in 2006,there were approximately 92,000 Americans waiting for an organ transplant but only 7,379 brain dead donors. That's one donor for every 12 patients. It's estimated that by the end of 2006, 6,570 people died waiting for an organ transplant.

 During the mid-90s,the transplant community started looking at coma patients, who still had some brain function, as a potential source for organ donations. These patients were categorized as "Donation After Cardiac Death,"or DCD. The label simply means the patient becomes a donor after a decision is made by their doctors or families to withdraw artificial life support, and the patient's heart stops. In 1995, there were just 64 DCD donors (1.2 percent of all dead donors). By 2006, that number had increased tenfold to 645. Most people don't even know there are now two separate categories of donor candidates. But those who do often see a vast ethical difference between the two. In the medical community, it's becoming a polarizing issue. Good people have strong, yet opposing opinions about the ethics of harvesting organs from coma patients. Should a life—no matter how diminished—be brought to an end? Should a life be artificially sustained when others could be saved?

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It is a giant question mark: What will happen to health care reform in America? This past week's election in Massachusetts has forced the president, Congress, and the country to take another hard look at the problems plaguing our system. Sunday, Dateline takes a look at the health care crisis through the eyes of American families who thought they were among the lucky ones: All had health insurance, and assumed they'd be covered when emergency hit. Turns out, they were in for the battle of their lives. NBC's Ann Curry reports on "Critical Condition."

Plus: A different kind of medical controversy, one that became a landmark legal battle. It involved an organ transplant, one of medicine's great miracles. Though transplants save thousands of lives every year, there is a shortage of organs, partly because of fear that the procedure could be abused. The dedicated young surgeon in this case was the first doctor accused of doing just that -- trying to save the life of one patient by hastening the death of another. Keith Morrison reports on "A Matter of Time." Click here for a sneak peek of this story.

Join us for a two-hour Dateline NBC on Sunday at 7 p.m. ET, 6 p.m. CT.

A mother of four disappears, vanishing in the night from her family's property on a vast wilderness. The next morning, they found her car at the foot of the driveway, but no body, no murder weapon, and no witnesses. You might think there wouldn't even be an arrest, let alone a trial. But there was a trial... and that's when things really got strange.

NBC's Keith Morrison goes inside The Mystery at Empire Lake.

See it all in this Friday starting at 9 p.m. ET, 8 p.m. CT.

In the first in-depth report on the thwarted Christmas terrorist attack, Chris Hansen investigates the main suspect in the case, and takes viewers through the events of what happened - and what could have happened - that day, and why so many warning signs went ignored. The report includes interviews with passengers and officials, and the first television interview with someone who spent time with the suspect while he was here in the U.S in 2008.

Then, double or nothing -- Hansen is back with another compelling hour on the Las Vegas undercover police operations where he gets exclusive access to go undercover with hidden cameras and confront criminal suspects.

See it all on a special Sunday Dateline NBC from 7-9 p.m. ET.