Skyfall — the 23rd entry in the James Bond franchise and the third to star Daniel Craig — hit U.S. theaters today, and critics are awarding it some of the highest marks in the series' 50-year history. But Skyfall's four-year production was nearly as convoluted and intriguing as the film that eventually resulted. Here, 007 fascinating behind-the-scenes facts about Skyfall:

001. Daniel Craig drunkenly offered Sam Mendes the chance to direct — without the producers' permission

The Hollywood Reporter reports that Skyfall first got off the ground when franchise star Daniel Craig bumped into director Sam Mendes at Hugh Jackman's 2009 birthday party in New York City. When Mendes tossed off a few casual remarks about how he would direct the next 007 film, Craig impulsively offered him the job. "I'd had a few too many drinks and I completely overstepped the line and said, 'Why don't you do it'?" said Craig. "And Sam said, 'Why not?'" Fortunately, producers Barbara Broccoli and Michael G. Wilson agreed.

002. It almost wasn't called Skyfall

After 22 films, producers had exhausted almost all of Bond author Ian Fleming's original titles, necessitating the invention of a wholly original title for the first time in Daniel Craig's tenure as Bond. While toiling for months under the workmanlike moniker Bond 23, producers considered the titles Silver Bullet, A Killing Moon, and Once Upon a Spy, finally settling on the terse, dramatic Skyfall.

003. Sean Connery's name came up in early casting brainstorms

Albert Finney delivers a pivotal turn as a figure from 007's childhood in Skyfall's final act, but another well-respected British actor was once mentioned for the role: Sean Connery. "There was a definite discussion about that," says director Sam Mendes, who ultimately decided that having a former Bond share the screen with Craig would prove too distracting: "Connery is Bond and he's not going to come back as another character."

004. It was timed to coincide with important dates in franchise history

Mendes was determined to make a Bond entry that hearkened back to the roots of the series, which began with 1962's Dr. No starring Connery. Consequently, several cast members, including series newcomers such as Berenice Marlohe, Naomie Harris, and Javier Bardem, were confirmed at a press conference held exactly 50 years after Sean Connery was announced as the original 007. And Skyfall's official theme song, as performed by Adele, was released 50 years to the day after Dr. No's release date in England — at 00:07 London time.

005. Whenever possible, Mendes avoided CGI

In keeping with Skyfall's retro feeling, Mendes insisted on using practical effects instead of CGI when he could. As a result, the movie gets by with only 500 CGI shots — far fewer than the count for other recent action hits like The Avengers, which boasts more than 2,200 effects shots.

006. Adele's theme song brought Craig to tears

According to director Mendes, British crooner Adele accepted the offer to write the film's title single reluctantly, worrying, "I write songs about myself, how can I make a Bond song?" But the soulful tune she eventually delivered managed to bring 007 himself to tears. "I cried," Daniel Craig told Yahoo! Movies. "From the opening bars I knew immediately, then the voice kicked in and it was exactly what I'd wanted from the beginning."

007. At least two more Daniel Craig-starring Bond films are on the way

In the wake of Skyfall's enormous success with both critics and international audiences, producers have made a deal with Skyfall writer John Logan (Gladiator, The Aviator) to pen two more Bond films with a single plot arc, says Deadline, the first 007 storyline to be played out over multiple movies. The films would be shot back-to-back, which means it likely won't take another four years before Bond 24 and Bond 25 — whatever their final titles turn out to be — are ready for release.