At this time last year, Universal Pictures was celebrating its first major box office success of the year, when Fifty Shades of Grey opened with a whopping $85.1 million in its debut weekend in theaters. Today, author E.L. James revealed on her Instagram page that filming is now under way on the highly-anticipated sequel Fifty Shades Darker. While we don't know exactly where production is taking place, hopefully we'll get to see more from the set soon.

Back in November, we reported that both Fifty Shades of Grey sequels, Fifty Shades Darker and Fifty Shades Freed, will be shot back-to-back. Universal has already set a February 10, 2017 release date for Fifty Shades Darker, with the finale Fifty Shades Freed arriving one year later on February 9, 2018. No official plot details have been released quite yet, but the E.L. James novel this sequel is adapted from opens with Anastasia Steele (Dakota Johnson) distancing herself from Christian Grey (Jamie Dornan).

The book follows Anastasia as she takes a job at a Seattle publishing house, although she still thinks about Christian constantly. Their affair is re-kindled when Christian comes up with a new arrangement, but Anastasia must face a number of women who came before her, as Christian tries to wrestle with his own inner demons. Anastasia also learns more about Christian's tormented past in this follow-up as well, but we don't know how closely sequel will follow the book quite yet.

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Fifty Shades of Grey director Sam Taylor-Johnson and Kelly Marcel both parted ways after the first movie opened. This paved the way for E.L. James' husband Niall Leonard (The Bill) to write the script, with James Foley (House of Cards) coming aboard to direct both sequels. Reprising their roles from the first movie are Max Martini (Taylor), Eloise Mumford (Kate), Luke Grimes (Elliot Grey), Rita Ora (Mia Grey) and Victor Rasuk (Jose Cunningham).

New cast members for this sequel include Kim Basinger as Elena Lincoln, Christian's business partner and ex-lover, Bella Heathcote as Leila Williams, another one of Christian's former submissives and Eric Johnson as Jack Hyde, one of Christian's business rivals. Arielle Kebbel has also signed on for the finale Fifty Shades Freed as Gia Matteo, a beautiful architect tasked with building Christian's new home in Seattle. While we wait for more details on Fifty Shades Darker, take a look at the first set photo below.