In a corridor deep inside Mattel's sprawling headquarters in El Segundo, California, a timeline on the wall marks the moments that shaped how the world plays. 1947: the plastic Uke-A-Doodle ukulele. 1959: Barbie's debut. 1968: Hot Wheels. 1992: UNO joins the family. But the most telling date might be 1955, when Mattel became a major sponsor of Walt Disney's The Mickey Mouse Club — one of the first toy company TV sponsorships, and the start of a partnership that still delivers. The newest fruit: Toy Story 5, hitting cinemas this week.

Mattel's campus is five hectares of main office tower, design centre, and studio operations building. It houses lawyers and accountants alongside product designers, sculptors, and 3D modellers. Engineers work in large-scale 3D printing centres creating prototypes. It's the real-world equivalent of Willy Wonka's Chocolate Factory — though there's no chocolate river. Getting inside is like finding a golden ticket, with much of research and development off-limits, but plenty of upcoming movie tie-ins on display.

"When Ruth Handler came up with the idea for Barbie, she came up with it because she was observing her daughter cutting out images from a magazine and trying to have an interaction with that in a two-dimensional way," says Nick Karamonos, Mattel's senior vice-president of action figures and entertainment partnerships.

The world's toy business is dominated by four companies: The LEGO Group (Denmark), Bandai Namco (Tokyo), Hasbro (Rhode Island), and Mattel. Bandai Namco's revenue outstrips competitors, but LEGO, Mattel, and Hasbro have stronger brand profiles in the US, Australia, Canada, and Europe. All four share a complex, data-driven relationship with consumers — but how the child feels is almost as important as how parents spend.

Product designer Baxter Crane and product design manager Kristen Sanzari say children shouldn't be underestimated. "They find new ways to play with anything so you really have to challenge them in every way that you can," Crane says. Sanzari adds that making the best Toy Story toy allows kids to "play out those stories in the movie and have it be authentic, but also then create their own Toy Story and imaginative creative play on their own."

"The need for kids to play, to use their imaginations, to have joy, to allow that to create social relationships with their friends and their peers, that is fundamental," says Karamonos. "So what we do is to always try to provide the tools and the experiences for that."

Karamonos says how kids reach Mattel and how Mattel reaches them is changing, but the fundamental nature of toys — what they create for humans — has been and will continue to be universal. "That's the beauty of this business and that's certainly the genius of Toy Story."

  • Mattel's timeline includes: 1947 (Uke-A-Doodle ukulele), 1959 (Barbie), 1961 (Ken), 1965 (See-'n-Say), 1968 (Hot Wheels), 1992 (acquired UNO)
  • 1955: Mattel sponsors The Mickey Mouse Club, beginning a 70-year Disney partnership
  • Toy Story 5 releases in cinemas this week
  • Mattel's headquarters: 5-hectare campus in El Segundo, California
  • The four dominant toy companies: LEGO Group (Denmark), Bandai Namco (Tokyo), Hasbro (Pawtucket, Rhode Island), Mattel (El Segundo)
  • Bandai Namco brands include Gundam, Dragon Ball, Tamagotchi; Hasbro owns Nerf, Monopoly, Transformers, Magic: The Gathering, Dungeons and Dragons