Rob Marshall—no relation to Gary Marshall, Penny Marshall, or Marshall Mathers—directed Chicago. As a young whippersnapper, he danced in Broadway shows, but after injuring himself in Cats, he went on to his second (of nine?) lives, in choreography and directing.
After directing a few TV adaptations of musicals, including Cinderella (1997) with Brandy and Whitney Houston, Marshall debuted on the silver screen with Chicago. And what a debut it was, winning the Director Guild of America trophy and being nominated for an Academy Award (but losing to Roman Polanski).
Marshall went on to direct more musicals—Nine (2009) and Into the Woods (2014)—and non-musicals—Memoirs of a Geisha (2005) and Pirates of the Caribbean: On Stranger Tides (2011).
Bill Condon has the weirdest resume in Hollywood. Prior to writing Chicago, he was predominantly known as a writer and a director. He wrote and directed the critically acclaimed Gods and Monsters (1998) starring Sir Ian McKellan and Brenden Fraser (that's Sir George of the Jungle to you). After writing Chicago (which he did not direct) he went on to write/direct Queen Bey's Dreamgirls (2006) and reunited with Ian McKellan in Mr. Holmes (2015).
However, there are also weird spots on there. Condon directed the sequel to Candyman, subtitled Farewell to the Flesh in 1995, and the two biggest spectacles of 2011 and 2012, which might be horror depending on your point of view: Twilight: Breaking Dawn Parts 1 and 2. Edward may have sparkled but we didn't see any jazz hands… so we don't know what all these movies have in common.
Chicago's jump (complete with jazz hands) from stage to screen was assisted by The Producer's Circle Company, which mostly produces theater, although it also produced, oddly, The Shining in 1980. (Alternate song lyric: "Who says that redrum's not an art?!") Co-producing was Storyline Entertainment, a studio that went on to produce the live television adaptation of Peter Pan starring Alison Williams and Christopher Walken.
Miramax is the little distributor that could. Founded in 1979 by two kings of Hollywood —Harvey and Bob Weinstein—Miramax was the little-big distribution company of the late '90s and early 2000s. It's not necessarily a small company but it's not a huge name either, like Universal Pictures or 20th Century Fox (although it was owned by Disney from 1993 to 2010). Miramax was the place for movies too big to be indie darlings, but maybe too niche to be blockbuster hits… although they definitely have their share of those.
Their most popular films include The Piano (1993), Pulp Fiction (1994), and Shakespeare in Love (1998) As you can see, the Weinsteins know how to find the sweet spot between box office smash and Oscar bait, and Chicago is smack dab at the intersection of both.
Chicago takes the staging of a Broadway show, combined with Fosse-inspired choreography that can't be beat, and adds it to more "realistic" scenes interspersed throughout to emphasize the fact that the musical numbers take place in the seclusion of Roxie's head.
Elvis Mitchell of the New York Times says Chicago had a long road from stage to screen. Fosse tried adapting the movie in 1979 as All That Jazz but it wasn't until 2001's Moulin Rouge that everyone realized that the big screen musical was back.
Mitchell praises Chicago's "bullet-timed editing and brassy, hip-shaking musical numbers" but steps a bit on Zellweger's blue suede shoes saying she has "two left feet." But thanks to the magic of movie editing (a trick unavailable in a live Broadway show) she still looks like she can hoof it.
Chicago is a musical.
(See where this is going?)
Without its catchy songs and jazzy numbers, it would be pretty darn boring. Person commits a crime. Wants to be famous. Yawn. That's a story we've seen in the real world plenty of times. But the music takes it to another level. It furthers the plot and explains the characters in a way that gets them stuck in your head.
Making it a musical leaves us in the audience singing and dancing along—and making us complicit in Roxie's rise to infamy. You may think she's reprehensible for cashing in on a crime, but it wouldn't happen if the public didn't love it.
The music in the film is closer to the 1975 original production, as opposed to the popular 1996 revival starring Bebe Neuwirth as Velma, which featured a few songs not in the film. John Kander and Fred Ebb are also responsible for the music in Cabaret (1972). These guys know their jazz.
Chicago the movie was a blockbuster success, but it's the musical that has the long-running fandom. The musical original ran from 1975-77, but was revived in 1996, and (as of 2015) it's been a non-stop jazz joint ever since. It is the second-longest running show, behind only that masked maniac The Phantom of the Opera. Maybe Roxie should drop a chandelier on his head to take the top spot.
Famous Roxies include Brooke Shields, Ashlee Simpson, Brandy, and Rumer Willis. And, as far as we know, they didn't have to kill anyone to get the role. So after you see Chicago streaming in the comfort of your own home, chances are good you can get your jazz fix on the stage, too.