'ER' Finally Checking Out After 15 Memorable Seasons

"Boom. Boom. Blanket. Boom."

Noah Wyle talks himself through each step as he walks deliberately across the "ER" trauma room set, from fetal monitor to glove dispenser and back to the gurney where his Dr. John Carter will help an intern deliver twins.

"It's a swaddle, right?" he asks, checking each move with medical technical adviser Jon Fong, M.D. "Baby, point, wrap, wrap, bundle."

Wyle has done this ballet — the Trauma 2 waltz — hundreds of times since NBC's groundbreaking medical drama premiered in 1994. But this is his last dance, one of a cascade of lasts for cast and crew that will be part of "ER's" two-hour series finale (Thursday, 9 ET/PT, after a retrospective at 8).

"My final trauma scene," says Wyle, one of many ex-regulars to return for goodbyes. "I've been on the gurneys as a patient, over the gurneys as a doctor, done a lot of chest compressions, thoracotomies and intubations, sewn a lot of sutures and snapped on a lot of latex gloves."

The scene, which not surprisingly has complications, completes the circle at Chicago's County General Hospital for the now-veteran Carter, who assisted on a delivery as a medical student in the long-ago premiere.

For the finale trauma scene, Wyle is one of a dozen people, including original nurse Yvette Freeman, navigating the small green room in the signature choreography that helped make "ER" one of TV's last super-hits and NBC its dominant network.

During "ER's" early years, it averaged more than 30 million viewers as TV's No. 1 show — peaking at 48 million for a 1995 episode — and spawned magazine covers, patient inquiries to doctors, Emmys (to date, a record 122 nominations) and an Oscar-winning movie career for George Clooney.

"It brought back hour dramas in a time where the sitcom was king," says executive producer Christopher Chulack, who says "ER" is leaving at the right time.

What was then an unusual style — constantly moving Steadicam shots, quick cuts, medical talk and disconnected dialogue — made NBC executives wary until it enthralled viewers, he says. "You felt you were a fly on the wall every Thursday night."

Now, reflecting its age, unavoidable repetition and a sharp decline in overall TV viewing, "ER" (9.3 million) is a shadow of that ratings powerhouse but still the No. 3 drama for faded NBC. It still attracts top talent, including Angela Bassett and Forest Whitaker.

Freeman, whose Haleh Adams has been part of "ER's" ever-reliable, recognizable nursing staff from the pilot, is proud the series received a fitting goodbye, with guest appearances through the season by "every star you can name," including Clooney. Thursday's episode features more: Sherry Stringfield, Laura Innes, Eriq La Salle and Alex Kingston.

"In the beginning, it was a touch of reality. It was fast-paced. … You got to know the patients more and their problems more," she says. "Then it got a little soapy." It also featured explosions, shootouts, a helicopter crash and a tank assault, the last based on a real event.

More recently, "ER" has become revitalized, she says. "Now it's come back to itself. It's one of the best TV shows ever, and I'm proud to be on it."

History, legacy and an enduring fondness are on the minds of those shooting the final scenes, including director Rod Holcomb, who also directed the two-hour series premiere. "Not only was the script really well-written by Michael Crichton and wonderfully produced by John Wells, but that cast — what a cast!"

A simple gurney wheel provided the inspiration for ER's seamless visual style, he says. "It turns, it tumbles, it twists. If you keep following and watch it long enough, you'll realize you've been through the entire 'ER' ward and not known it."

Wyle, who says "ER" may have gone on a little longer than ideal, is pleased with the quality of the final season, and with the legacy of the series. "It was fairly innovative in pace and style," he says.

"We would tell the stories in a piecemeal fashion, only catching the end or beginning of an arc, which reinforces the notion that the 'ER' is a transitional place where you don't necessarily know where they're coming from or going to," Wyle says. "They're just passing through."