Bob Iger has repeatedly called it the “highest priority” of the Walt Disney Co.

The launch of Disney Plus has become the talk of the entertainment industry — for creatives, for tech mavens and for Wall Street — as production and development of original series and movies accelerate for the streaming service, slated to debut in the U.S. by year’s end.

Disney, under the leadership of chairman-CEO Iger, has re-engineered its operating segments and reshuffled its management ranks to prepare for its streaming future. The Burbank media giant has made big investments in technical infrastructure. And Iger rocked the Hollywood establishment in 2017 with his dogged pursuit of Rupert Murdoch’s 21st Century Fox entertainment empire. He was hunting for the kind of IP that can help drive Disney Plus and future platform offerings, and lend itself to exploitation through Disney’s well-oiled franchise machine.

Now that the Fox acquisition is near the finish line, with a projected close by March, industry sources say pressure is mounting inside Disney’s film and TV units to grapple with the force of a number of headwinds at once. They’re tasked with stepping up their overall output — significantly in the case of its movie units — at a time when they’re also bracing for what will surely be a massive process of integrating the contingent of Fox executives who will make the transition.

Layoffs of duplicative staffers are expected to reach into the hundreds, perhaps thousands. Adding still more drama, the end of the Fox merger limbo starts the beginning of a potential rivalry between Kevin Mayer, the Disney veteran overseeing the Direct-to-Consumer and International division, and Peter Rice, the long-serving Fox executive who is the incoming chairman of Walt Disney Television, to succeed Iger as CEO. A senior Disney TV executive described the atmosphere at the Burbank studio as “tense.”

It’s become clear to Disney watchers that Iger — who says he plans to step down when his contract expires in 2021 — has staked part of his legacy on proving that the empire can strike back against Netflix and the upstarts that have so dramatically disrupted Hollywood’s old order. Insiders say the chief executive has been taking a strong hand in leading programming check-in meetings with the company’s various divisions.

Questions about how it will manage the transition from traditional distribution models into the walled garden of direct-to-consumer services are so numerous that Disney has scheduled an Investor Day presentation on the topic for April 11. The company is also hoping to dazzle with a demo of the service and a sneak peek at some of the programming in the works.

Wall Street sources say Disney will have to shed light on three key points in pitching the streaming strategy to investors: how much it will spend on content, how much traditional licensing revenue will be lost by keeping more of its content in-house, and when it expects the bottom of that investment cycle to come before a return to growth. That’s a tall order.

“It’s going to be years until they start to recover their investment in streaming,” says Hal Vogel, veteran industry analyst. “They will be forgoing high profit margin revenues and moving into a very competitive arena with Netflix and Amazon and probably Apple. Investors are focused right now on the dream of seeing everybody move into streaming. But we need to know more about what the pain points are for these companies and how much they are willing to lose.”

More details about Disney’s investment to date in its Direct-to-Consumer operations will be forthcoming on Feb. 5, when the conglom reports its fiscal first quarter earnings. For the first time, the company will break out financials for the Direct-to-Consumer and International division. Disney earlier this month disclosed that the unit recorded a loss for the first nine months of 2018 of $738 million in operating income on revenue of $3.4 billion, most of which came from Disney’s international channels.

Disney is up to the huge challenges ahead, in the view of RBC Capital Markets senior media analyst Steven Cahall. He estimates the company will devote about $500 million to original programming for Disney Plus in 2019. “Disney spends more on content than anyone else globally. It has decades of experience in making excellent content, it has a huge balance sheet with low leverage and it’s a brand that’s known the world over,” Cahall wrote in December.

RBC research pegs Disney as the biggest spender among media giants on content, with a projected $23.8 billion for 2019, or $16.4 billion excluding sports-related properties. Disney’s total spending to fill its pipeline amounts to 22% of the estimated $107 billion in global content spending among the largest media companies. AT&T and Netflix are next on the list with $14.3 billion and $14 billion, respectively, per RBC.

Disney declined to comment for this story.

With so much on the line, insiders are increasingly scrutinizing the programming plans for Disney Plus as well as the team assembled to execute the service. There’s little doubt that the streaming venture will rise or fall largely on the popularity of its original content. In that context, questions have been raised in the creative community about the absence (so far) of deeply experienced programming executives at the top of Disney Plus.

Disney’s approach has come into sharp focus as its largest traditional competitors — NBCUniversal and WarnerMedia — in recent weeks have tapped veterans Bonnie Hammer and Kevin Reilly, respectively, to lead programming for streaming efforts that aren’t nearly as ambitious at the outset as those of Disney Plus.

Ricky Strauss, who spent the past six years as head of film marketing for Disney, was named president of content and marketing for Disney Plus in June. Agnes Chu was tapped to oversee content shortly after Disney disclosed its intent to launch the service in August 2017. She’s a senior VP who was a story and franchise development executive at Walt Disney Imagineering. She worked as VP in the office of the chairman-CEO and was a close aide to Iger from 2013-16. Before that, she spent three years as director of daytime and current programming at ABC, where she supervised “General Hospital” and primetime comedies “Malibu Country” and “Don’t Trust the B—- in Apt. 23.”

Leading the charge at the top is Mayer, with the Direct-to-Consumer and International division created last March to house Disney Plus and its eight-month-old counterpart ESPN Plus. Mayer had been head of corporate strategy and business development since 2005. He’s been Iger’s right hand on the studio acquisition spree — Pixar, Marvel, Lucasfilm and most recently 21st Century Fox — that turbo-charged Disney into the world’s largest media company.

Strauss and Chu are each accomplished executives who are known to be well respected by their peers inside and outside Disney. They obviously have Iger’s vote of confidence. But there’s no disputing that neither has extensive experience in managing high-end TV series productions. Strauss served as head of production for Participant Media before Disney. Chu worked in documentary production before joining Disney in 2008 to develop digital content.

Iger has been weighing in on plans for big-ticket projects such as “The Mandalorian,” the first-ever live-action “Star Wars” series, which is sure to be a big selling point for Disney Plus. While Disney has bluntly stated that its streaming service will not try to match Netflix in terms of sheer volume of originals, sources say Iger has of late pushed the team to stoke the development pipeline to ensure a steady stream of fresh content can land on Disney Plus in the months after its launch.

At the same time, sources say Iger sees much of the creative spark for Disney Plus as coming from the creative teams behind the studio’s four content brands that will populate the service: Disney, Marvel, Lucasfilm and Pixar, as well as Fox’s main operating units, including FX, Fox Searchlight and National Geographic and its prestigious documentary vault.

A source close to the situation says there was a belief that executives from backgrounds other than traditional primetime TV might be better suited to building a new-paradigm programming operation. Chu’s team has been augmented in recent months with the hiring of Sarah Shepard, formerly of Smokehouse Pictures, as VP of scripted content and Marvel alum Dan Silver as VP of unscripted.

“We have the luxury of programming this product with programs from those brands or derived from those brands, which obviously creates a demand and gives us the ability to not necessarily be in the volume game, but to be in the quality game,” Iger told Wall Street analysts in August.

Insiders say the thinking is that as a strictly VOD platform, the programming management needs of Disney Plus are different from that of a traditional network with a development and greenlighting hierarchy. And it has been emphasized that feeding strong content to Disney Plus is meant to be a holistic effort among all of the company’s content-producing units. Marvel, Lucasfilm and Pixar have long operated with a great deal of autonomy in plotting their film and TV projects, albeit with support from the Walt Disney Studios operation headed by Alan Horn and from network partners.

On the series side, as development began to ramp up last year, there was confusion about how Disney Plus would handle dealmaking and the always-contentious issue of profit participation points for talent. Disney ultimately settled on a formula for “buying out” points up front — much as Netflix, Amazon and HBO do — because there will be no aftermarket sales of the titles to split among participants. Sources describe the Disney Plus formulas and pay scales as generous for Marvel- and “Star Wars”-branded productions — “They’re spending real money on those shows,” says one top TV agent — but that other productions are offering less lucrative deals than comparable projects would likely command at Netflix or Amazon.

Others say the structure at Disney Plus has made it a little unwieldy to make deals for shows and also more difficult to pitch concepts and talent to the service. “Do you pitch Agnes? Do you pitch Jeph [Loeb, Marvel’s TV chief]? It’s not clear yet which door gets you in,” says another veteran agent.

Original movies are slated to be a big part of the Disney Plus lineup. At first, industry sources say the message from the Disney Plus team last year was that it was looking for modestly budgeted movie concepts. Then came word that it is open to projects with a wider budget range of $20 million to $60 million. Sean Bailey, president of motion picture production for Disney Studios, is playing a major role in liaising with the imprints and helping to steer the movies strategy. Other projects are coming from the seasoned team at Disney Channels Worldwide, which has long produced telepics.

Strategy adjustments and dealmaking hiccups are hardly unexpected for such an expansive start-up effort. Sources close to the situation point to the hiring earlier this month of Fox alum Joe Earley as exec VP of marketing and operations for Disney Plus as recognition that more heft was needed to prepare for the launch. Earley had a 21-year run at Fox Broadcasting, rising to chief operating officer for Fox Television Group. He spent the past three years as president of Gail Berman’s Jackal Group shepherding TV, film and legit productions. Earley will soon be joined under the larger Disney corporate umbrella by a host of former TV and film colleagues from 20th Century Fox.

Walt Disney Television chairman Rice and Disney Television Studios and ABC Entertainment chairman Dana Walden, the Fox executives who will take on the top TV leadership roles at Disney (excluding ESPN), will be involved in feeding content to Disney Plus through their oversight of the combined ABC Studios and 20th Century Fox Television operations. Disney’s master plan for how Disney’s and Fox’s existing production units in film and TV will be integrated — or whether they will remain separate imprints — is still being sorted out.

“There are a lot of [Disney and Fox executives] out there still waiting to see where they’re going to go,” notes a TV industry vet.

Corporate integrations on the scale of Disney and 21st Century Fox are famously fraught with unexpected obstacles (think AOL-Time Warner). Political battles and turf wars are commonplace in any such melding of operations, particularly those with such distinctly different corporate cultures as Disney and Fox. The perception that Mayer and Rice are in a foot race to the CEO suite — rightly or wrongly, that’s the conventional wisdom in Hollywood — could add a wrinkle to the mandate for DTC/International and Walt Disney Television to work together in the enlarged Disney sandbox.

Executives in Burbank and Century City are bracing for a post-merger roller-coaster ride. The industry is waiting to see how Disney marshals its brand firepower for the streaming age. Disney’s board of directors no doubt has its eye on how the Disney Plus launch process plays out across the company as it evaluates successor options for Iger.

“It’s going to be Mr. Toad’s Wild Ride around here for a while,” says a longtime Disney insider.