If you flipped on Netflix at all this holiday season you no doubt noticed the novel new documentary series, The Toys That Made Us. The eight-part documentary series covers the secret history of the world’s most important toy lines, including G.I. Joe, Barbie and Star Wars. Polygon sat down with series creator Brian Volk-Weiss to preview the final four episodes, and talk about the work that went into pulling it all off.

What makes Volk-Weiss’ show such interesting television are the first-hand accounts used to tell the story. The format isn’t something as tawdry as a cavalcade of B-list celebrities telling us about their favorite He-Man figures while old commercials roll in the background. His team of researchers and producers spent years running down the artists, designers and executives who created and marketed these products and put them in front of the camera.

If you only watch one episode, make it the first one covering Star Wars. In it, the team sits down with Jim Kipling, the lawyer at Kenner who negotiated the original licensing agreement with George Lucas. Volk-Weiss told Polygon that, ever since it was signed in the late 1970’s, Kipling has never once agreed to be interviewed about those negotiations.

“It took awhile to convince Mr. Kipling to do the interview,” Volk-Weiss said. “Up until he walked in the door, we weren’t even sure if he was going to show up. We certainly did not know he was going to come in with the original paperwork like he did, either. I’ve interviewed hundreds and hundreds of people over the course of my career, [but he] ended up answering pretty much every question with the greatest detail possible.”

The Toys That Made Us: Star Wars Star Wars toys forever changed the way we play! Check out the opening of our Star Wars episode, streaming now on Netflix! #TTTMU Posted by The Toys That Made Us on Saturday, December 23, 2017

Even more astounding is the level of access The Toys That Made Us team was given to high-level executives within the toy industry. Later, in that same episode, a former CEO of Hasbro admits on camera that he almost torpedoed the deal to renew the Star Wars rights with LucasFilm and, with that one mistake, put the entire company at risk.

Those kinds of candid conversations, Volk-Weiss said, will carry through into the second half of the season, which will feature intimate accounts of the creation of Hello Kitty and the Transformers.

Another common theme will be the relentless cycle of boom and bust that even the biggest names in the toy industry have endured over the years. None of them were more hair raising, Volk-Weiss said, than the story of Lego.

“Literally, Lego was three months from lights-out,” Volk-Weiss said. “They were actively engaging with Mattel about a takeover which, by the way, Mattel walked away from. ... Everybody we talked to there, everyone talks about it all the time. It’s really in their culture and their DNA, the lessons they learned from almost going out of business.”

The most challenging episode to make, Volk-Weiss said, was the upcoming show on the Star Trek toy lines. That’s because there were simply so many disasters to catalog.

“Todd McFarlane is doing Star Trek toys now,” Volk-Weiss said, “But before that, there was Playmates. ... They just went crazy! ... With Star Wars, Kenner had one failure — the Micro Collection — but everything else, to a certain extent, was either a home run or a grand slam. With Star Trek, you literally had failure after failure.

The Toys That Made Us: Barbie Iconic. Legendary. Barbie! Check out the intro to our episode all about Barbie and then head to Netflix to watch the whole thing, now streaming! #TTTMU Posted by The Toys That Made Us on Tuesday, December 26, 2017

“They always made toys for the wrong movie. The original Star Trek movie? Failure. Lots of toys. Star Trek 2: The Wrath of Khan? Huge hit! No toys. Star Trek 3: The Search For Spock? Barely a hit, lots of toys. Star Trek 4: The Voyage Home? Biggest hit in the original movies. No toys. ... It’s literally just a comedy of errors.”

The biggest name that agreed to be interviewed for the series was director Michael Bay, who will appear on camera later this year to talk about the Transformers. But the most interesting interview for toy collectors and fans, Volk-Weiss said, will be designer Keiichiro Sakuma.

“We tracked down the guy who helped design the original mechanisms of Optimus Prime,” he said. “He’d never done an interview before. He didn’t speak a word of English and, you know, to describe his demeanor when he walked into the room, I think he thought he was having a practical joke played on him. He simply couldn’t believe Netflix wanted to talk to him.”

Volk-Weiss said it was a mad scramble to get the first four out in time for the holidays, and he still has two more left to edit. No release date has been set for the final four episodes, but the team has said on Facebook they should be out sometime in the next four months.