The actress spoke to Entertainment Tonight yesterday, to confirm that work on the film will begin as soon as she's wrapped Big Little Lies season 2.
"Oh it's gonna be so fun!" she said. "I got to go to a meeting the other day where we talked about all the new plot points and all the characters and some returning characters and some new characters. I mean, I got so excited just in the meeting. I was like, 'This is gonna be good.'"
What did we glean from this? That there will be returning characters (we're keeping fingers crossed for Jennifer Coolidge's Paulette), as well as some new additions. As writing is actively underway, we could expect casting announcements shortly...
Following a report by Deadline earlier this year, which first suggested that production of the third instalment had been given the go ahead, Witherspoon took to Instagram to confirm the happy news.
"It's true... #legallyblonde3," she wrote, alongside a video of her lying on a pool float in a pink sequin bikini, which looks very similar to a scene from the first film. While dropping references to the previous movies as hints.
It's believed that the deal with MGM Studios will see them bring back much of the same creative team that worked on the first hit film. Kirsten “Kiwi” Smith and Karen McCullah, who originally adapted the Amanda Brown novel for the 2001 film, are in final talks to write the script. This time Witherspoon will also take on a producer role via her Hello Sunshine production company.
Incredibly, it's been 17 years since the original film hit cinemas. The sequel, Legally Blonde 2: Red, White & Blonde, followed two years later in 2003.
The original film grossed more than $140 million on a budget of just $18 million. It was later adapted into a hit stage musical which continues to tour around the world.