It was written and directed by Phil Lord and Christopher Miller from a story they co-wrote with Dan and Kevin Hageman, based on the Lego line of construction toys.

The film was dedicated to Kathleen Fleming, the former director of entertainment development of the Lego company, who had died in Cancún, Mexico, in April 2013.

Soon after, Bad Cop's forces attack and capture everyone except Emmet, Wyldstyle, Vitruvius, Batman, and fellow Master Builders MetalBeard, Unikitty, and Benny.

Business decapitates Vitruvius and throws the Piece of Resistance into an abyss before arming a device to execute all the captured Master Builders.

Strapped to the mechanism's battery, Emmet flings himself off the edge of the tower and into the abyss, disarming the device and saving his friends and the Master Builders.

Inspired by Emmet's sacrifice, Wyldstyle, who reveals her real name to be Lucy, rallies the Lego people across the universe to use whatever creativity they have to build machines and weapons to fight Business's forces.

The abyss transports Emmet to the human world, where the events of his life are being played out in a basement by a boy named Finn on his father's Lego set.

Finn's father, revealed to be the Man Upstairs, chastises his son for creating hodgepodges of different playsets and begins to glue his perceived "perfect" creations together permanently.

Finn's father reconciles with his son, which plays out as Business reforming, capping the Kragle with the Piece of Resistance, and ungluing his victims with mineral spirits.

Additionally, Anthony Daniels, Keith Ferguson, and Billy Dee Williams appear as protocol droid C-3PO, and smugglers Han Solo and Lando Calrissian from the Star Wars franchise.

Dave Franco, Jake Johnson, and Keegan-Michael Key portray Emmet's co-workers Wally, Barry, and Foreman Jim, respectively.

Warner Bros executive Kevin Tsujihara, who had recognized the value of the Lego franchise by engineering the studio's purchase of Lego video game licensee Traveller's Tales in 2007, thought the success of the Lego-based video games indicated a Lego-based film was a good idea, and reportedly "championed" the development of the film.

Nevertheless, Lego's vice president of licensing and entertainment Jill Wilfert responded positively to the Hagemans' treatment that Lin pitched.

By this time, animator Chris McKay, one of the directors, producers, and editors of Robot Chicken and Moral Orel, had joined Lord and Miller to co-direct.

We took something you could claim is the most cynical cash grab in cinematic history, basically a 90 minute LEGO commercial, and turned it into a celebration of creativity, fun and invention, in the spirit of just having a good time and how ridiculous it can look when you make things up.

Lord recalled that Superman was omitted for an extended period of time due to a lawsuit against Warner Bros. by the heirs of co-creator Jerry Siegel, before being reinserted at the last minute.

The film also features Billy Dee Williams and Anthony Daniels reprising their roles as Lego iterations of their Star Wars characters Lando Calrissian and C-3PO respectively from the original movies while Keith Ferguson reprises his role as a Lego version of Han Solo from Robot Chicken, replacing original actor Harrison Ford.

Lin recalled the closure of their deal to feature the characters as hectic, as The Walt Disney Company announced their purchase of Lucasfilm a few weeks after the filmmakers had traveled there and received permission to include them.

[35] In the film's live-action segment, Finn returns Emmet to the Lego world via an arts-and-crafts-covered tube labeled "Magic Portal", which production designer Grant Freckleton confirmed was a direct reference to Australian filmmaker Lindsay Fleay's 1989 animated short film The Magic Portal, which similarly incorporated live-action segments.

[7] The film's original score was composed by Mark Mothersbaugh, who had previously worked with Lord and Miller on Cloudy with a Chance of Meatballs (2009) and 21 Jump Street (2012).

The single, released on January 23, 2014, is performed by Tegan and Sara featuring The Lonely Island (Andy Samberg, Akiva Schaffer, and Jorma Taccone), who wrote the rap lyrics, and is played in the film's end credits.

[8] Deadline Hollywood calculated the film's net profit as $229 million, accounting for production budgets, marketing, talent participations, and other costs; box office grosses and home media revenues placed it third on their list of 2014's "Most Valuable Blockbusters".

The critical consensus reads, "Boasting beautiful animation, a charming voice cast, laugh-a-minute gags, and a surprisingly thoughtful story, The Lego Movie is colorful fun for all ages.

[52] Michael Rechtshaffen of The Hollywood Reporter wrote, "Arriving at a time when feature animation was looking and feeling mighty anemic...The LEGO Movie shows 'em how it's done",[72] with Peter Debruge of Variety adding that Lord and Miller "irreverently deconstruct the state of the modern blockbuster and deliver a smarter, more satisfying experience in its place, emerging with a fresh franchise for others to build upon".

[73] Susan Wloszczyna of RogerEbert.com gave the film four stars out of four, writing, "It still might be a 100-minute commercial, but at least it's a highly entertaining and, most surprisingly, a thoughtful one with in-jokes that snap, crackle and zoom by at warp speed.

"[75] Drew Hunt of the Chicago Reader said the filmmakers "fill the script with delightfully absurd one-liners and sharp pop culture references",[76] with A. O. Scott of The New York Times noting that, "Pop-culture jokes ricochet off the heads of younger viewers to tickle the world-weary adults in the audience, with just enough sentimental goo applied at the end to unite the generations.

"[77] Claudia Puig of USA Today called the film "a spirited romp through a world that looks distinctively familiar, and yet freshly inventive.

"[79] Joel Arnold of NPR acknowledged that the film "may be one giant advertisement, but all the way to its plastic-mat foundation, it's an earnest piece of work—a cash grab with a heart".

[81] Michael O'Sullivan of The Washington Post said that, "While clearly filled with affection for—and marketing tie-ins to—the titular product that's front and center, it's also something of a sharp plastic brick flung in the eye of its corporate sponsor.

"[84] Sandie Angulo Chen of Common Sense Media gives a rate of four stars out of five, saying, "It's a testament to the veteran animation filmmakers that this one is so smart, humorous, and visually fun to watch."