Brian Williams may return to "NBC Nightly News" this August, or he may not. The debate continues in TV news circles. But an imminent appointment at the top of the news division is about to change the tenor of that debate: former NBC chief Andy Lack is poised to return.

Who is Lack and why is this second act considered so important to Williams’ potential survival?

Because as former NBC News president, he helped orchestrate Williams’ eventual ascendance at “Nightly.” Almost reflexively among industry observers, he’s considered a Williams supporter -- and one source even tells me he was consulted in an advisory capacity about Williams’ suspension, and pushed for a shorter one (three months) instead of the six-month-without-pay penalty he ended up with.

So: Good news for Williams? Almost certainly, But some sobering perspective:  

Lack, after all, will have other pressing challenges when he returns, possibly by next week, and they are huge: The short list: the “Today" show, MSNBC, and CNBC...

Details of the appointment were laid out in a Cynthia Littleton scoop in Variety Tuesday: Lack, 67, is expected to assume operational responsibility over all NBC News programming, including MSNBC, leaving Pat Fili-Krushel, its chair, and Deborah Turness, NBC News chief, in limbo.

Lack left NBC in 2003, following a bitter break with Bob Wright, who had brought him to NBC News in April 1993 to repair a deeply dispirited news division that had lost its footing after the "Dateline" exploding-pickup truck scandal.

Brian Williams had arrived at NBC News a month earlier.

Meanwhile, Lack’s expected appointment -- coincidentally, or not --  comes on the eve of two major stories about NBC News’ travails, in New York Magazine and Vanity Fair. Both are expected to lay out in considerable detail the long, slow decline of NBC's once-gilded, now-tarnished "informational" venues, notably CNBC and MSNBC. Indeed, the loss of Williams -- even for six months -- is a relatively minor blip compared to the massive challenges ahead at MS and CNBC.

And then, there's the "Today" show, NBC’s most important franchise, which remains (euphemistically) in “turnaround” mode.

 But at least for the moment, let's all agree that Williams is Job One.  

So, who is Lack? Before we get to that, let's sort out a couple of things. This appointment could not have happened without Tom Brokaw's blessing. Brokaw had been instrumental in bringing Lack to NBC 22 years ago. He is instrumental now.

The reason simply is that 22 years ago, Lack arrived at a place that had exploded along with that fated truck -- "Dateline," the news division's only successful news magazine in history, seemed almost certainly doomed, while the esprit of an entire once-proud news division had been vaporized. The former president, Michael Gartner, had whipped NBC News into financial shape -- but had little to no vision for the on-air product. He had alienated most of the staff... and then came the "Dateline" debacle.

Lack's role was deceptively simple: Settle the place down, and re-focus NBC News on the news, and new projects and new magazines.

His appointment at the time was met with...puzzlement. He'd had a long career to that point at CBS News (and there had created two newsmagazines, "West 57th" and "Face to Face with Connie Chung.") But he was not widely considered a leadership type -- too mercurial...too emotional...a screamer, even... He was absolutely considered a creative type who was uninterested, or unskilled, in the art of dispensing soothing management bromides.

Here's what Brokaw told the LA Times when Lack was appointed: "We're still in the hard-news business, but news divisions also are in the newsmagazine business today. We've had too many administrators and too few producers in the job in recent years. Andy is a smart, sophisticated producer with a lot of creativity and energy, and I'm delighted that he's coming here."

And then, the greatest of surprises: Lack succeeded beyond all expectations, possibility even Brokaw's. The NBC News rebuild began in earnest almost immediately. One of Lack's shrewdest moves -- a sustained effort to lure Diane Sawyer from ABC News to anchor a handful of primetime magazine shows, most likely "Dateline." He didn't get Sawyer, but he got the real estate. Soon, "Dateline" -- under the aegis of Neal Shapiro -- was to become one of the most important programs on all of NBC.

Before long, Lack's portfolio grew -- as overseer of MSNBC, where he made Williams a prominent primetime anchor. Williams 9 p.m. news broadcast lost and lost badly to Fox News -- but that wasn't the point, really. The point was to prepare Williams to succeed Brokaw.

Brokaw -- who had wanted to step away from “Nightly” for a few years, even before Lack had arrived - --, had considered an offer from "60 Minutes," another from ABC. They were non-anchor gigs that would have afforded him time to do what he really wanted to do -- write, travel, and of course continue to work as a prominent journalist. But loyalty anchored him at NBC.

Nevertheless, he still wanted a succession plan and expected Lack to implement one. Williams wouldn't simply be part of that succession plan -- he WAS the succession plan.

As Lack -- certainly under Brokaw's advisement -- saw it, Williams was the future.He had the goods: Resourceful on the air, likeable, and square of jaw, he seemed like the kind of guy who fit the Compleat Anchorman description.

There were of course chinks in the perfection, but then there had been with Brokaw  too decades earlier. Williams seemed a bit callow, too eager, even a bit too chatty -- even loquacious -- on the air. “Dead air” certainly would not be a risk with Williams.

 He needed time, visibility, and seasoning. He needed to be carefully groomed because -- while this may be hard to fathom now, in 2015 -- the idea of an "anchor succession" on one of the evening news programs was considered almost inconceivable.

How to do a succession? No one really knew, exactly. There wasn't exactly a playbook, after all, while the three-anchor triumvirate -- Brokaw-Rather-Jennings -- had been in place for decades.

These three weren't merely symbols of their respective news divisions, but symbols of TV journalism, of even their respective corporate empires…

Moreover, there was a pervasive sense at the time that the evening news shows were dinosaurs lumbering toward -- if not extinction -- then a diminished future.

How to replace the most popular of these three anchormen?

That fell to Lack, and Williams was receptive. He was shortly named chief White House correspondent, a job formerly held by Andrea Mitchell. It was as strong a signal as Lack could have made -- THE heir apparent was in place.

Lack would eventually be named NBC president, but that job never suited him. The overall sense was that the gig was just a rung -- to Wright's job, as head of the entire NBC Universal portfolio. Wright knew it, and there was friction.

Meanwhile, MSNBC was struggling, and Lack redoubled his efforts there, but to absolutely no avail. Shows and anchors were switched in and out, viewers fled, and suddenly MS was in crisis mode. It has never recovered.

Then Lack left, to run Sony -- lured there by his former friend and colleague, Howard Stringer, who was head of the whole shebang -- where, ironically, he built a reputation as a cost-cutter.

Neal Shapiro, Lack's successor, would then finish the job Lack and Brokaw had started, by installing Williams as anchor of "Nightly News" in 2005. Shapiro, in fact, was a key player -- arguably THE key player -- in the NBC News turnaround story. But struggles at “Today” would seal his exit. Lack got credit for the Williams' succession, none of the blame for MS’s woes.

Lack's expected appointment is certain to launch deja-vu-all-over-again speculation-- indeed, it already has, as this post indicates.

He’s back for at least one key reason -- to save the anchor who was once deemed 'too big to fail." But there are even more pressing reasons. Williams may have to wait in line.