It's the mind-bending thriller from Christopher Nolan starring Leonardo DiCaprio and so many of his usual suspects that we love. However you interpreted that ending, one thing is certain: Inception gives us plenty to think about, movie fans. Here we'll take a look at 10 things you never knew about Inception.

A freudian slip.

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Rather than weigh in with a definitive answer, Christopher Nolan carefully protects the ambiguity of the film's ending, allowing movie fans and film scholars the space to debate what's real. The writer/director did reveal some of the movie's influences, however. In addition to the myriad myths, music, and religious history incorporated in Inception, Nolan cited the work of Ian Fleming, the Wachowski siblings, and Sigmund Freud in a 2010 LA Times interview.

The dream team.

Nolan relied on his own experiences rather than volumes of research when it came to dreams as he penned this passion project over a period of several years. He also stuck with what he knew in another way: the Inception crew has roles that are analogous to different jobs in filmmaking. DiCaprio's character directs; Joseph Gordon-Levitt is the producer; Ellen Page, production designer; Tom Hardy, actor; Ken Watanabe, the studio; and Cillian Murphy, the audience.

A dreamy lead.

Warner Bros. executives have said the role of Dom Cobb was offered to Brad Pitt and Will Smith, but once Nolan had Leonardo DiCaprio in place, the director built the rest of the cast around him. He focused on hiring a lot of younger actors in order to make sure Leo didn't look too young to be in charge. Furthermore, Nolan revealed to the Hollywood Reporter that his star "made some extraordinary contributions to the script." The filmmaker's wife and producing partner, Emma Thomas, said DiCarpio helped make the movie "less of a puzzle and more of a story of a character audiences could relate to."

Dream casting.

A potential Titanic reunion sunk when Kate Winslet said no to playing Mal. James Franco was offered the part that went to Joseph Gordon-Levitt, but had a scheduling conflict. Don Johnson turned down the role of Peter Browning. After Evan Rachel Wood passed on the part that eventually went to Ellen Page, others rumored to have been in the running include Rachel McAdams, Emily Blunt, Carey Mulligan, Emma Roberts, and Taylor Swift. While she may not have been the first choice, it's been reported that Page was hired without an audition.

Dream Warriors.

Combining the first letters of the main character's names produces the word "DREAMS." Add the first letters of some of the supporting character's names gives us "PAY." Yes, for the crew assembled in Inception, DREAMS PAY.

What's in a name.

Speaking of names, there's even more to unpack with Dom Cobb. DiCaprio's character is driven by his desire to return home. In Russian and most Slavic languages, a word for home is "Dom." Like "domicile," it's rooted in the Latin word "Domus." The last name Cobb has a special significance, too. In Urdu, Sanskrit, Hindi, and Punjabi, "Cobb" phonetically (khwab) means "dream."

Searching for scarecrow.

We aren't done with the cool names in Inception! Cillian Murphy, who auditioned for Bruce Wayne and ended up playing the Scarecrow in Nolan's Batman trilogy, was given the Inception script and invited to choose a supporting role for himself. His character, Robert Fischer, was named after champion chess player Robert Fischer, subject of the 1993 movie Searching for Bobby Fischer. Believe us, there are even more names to unpack further down the Inception rabbit hole.

Last night I dreamt that somebody loved me.

Inception has a connection to The Smiths! Johnny Marr, the band's cofounder and legendary Morrissey collaborator, played guitar as part of Hans Zimmer's score. Since The Smiths ended, Marr has played in The The, Electronic, and Modest Mouse, to name but a few bands, and made guest appearances on records by Billy Bragg, Pet Shop Boys, Oasis, Pearl Jam, and many more.

A dreamy tune.

We can't talk about Inception without talking about those BONGS. We can thank the song "No, I'm Not Sorry for Anything" by late French singer Edith Piaf, which Nolan wrote into the script and asked Zimmer to work into the score. We hear bits of the song slowed down, including those bongs, which are slowed down trumpets. The song itself is 2 minutes and 22 seconds long. The movie's run time is 2 hours and 22 minutes. Incidentally, frequent Nolan collaborator Marion Cotillard won an Oscar for her 2007 portrayal... of Edith Piaf.

All in the family.

Speaking of frequent collaborators, Christopher Nolan's cousin Miranda Nolan plays a stewardess in Inception and shows up as a maid in The Dark Knight Rises.