Miranda Rae Mayo has teased Sex and the City star - and her Chicago Fire co-star - David Eigenberg with a fitness challenge, as the pair resume filming of season 10.
Miranda took to Instagram to share a video of her plank, tagging David - who is also currently filming the new reboot And Just Like That, with Sarah Jessica Parker and Cynthia Nixon - and showrunner Derek Haas.
"Coming for you Herrmann," she captioned the post, a reference to David's character Christopher HerRmann - also her boss at Molly's bar - being a lieutenant at Firehouse 51 and Miranda's character Stella Kidd passing the lieutenant exam at the end of season nine, paving the way for her to potentially take his position.
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She tagged the post with Beyonce's Run The World (Girls), another reference to their character's rivalries.
The two once competed for who was the best bar manager and are often seen challenging each other to become better firefighters.
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In the final episodes of season nine, Stella passed the exam to move up the ranks, but with no open lieutenant spots on Truck 81 or Engine 31, it remains unclear where fans will see Stella in the opening episodes of season 10.
Miranda challenged David on her Instagram
Miranda previously told HELLO about her own hopes for season ten and where her character, Stella, may end up when the show returns.
"I would like to see her get a position as a lieutenant at another house, and I would love to see her learn what it means to be a leader not in the place where she came up - that is really what I want to see for her," she said.
"How she confronts those challenges, of what works and doesn't work, confronting her past trauma and her childhood, her parents not being around, I would love to see that."
Kidd and Herrmann work together at the CFD and Molly's Bar
Season nine ended with a major cliffhanger, as Squad Three attempted to save a victim whose boat was capsized, only to find the boat collapse on top of them.
As the episode faded to black, Kelly Severide and Joe Cruz, as well as colleagues Capp and Tony, were seen gasping for air as the water rose above them.
Back on shore, the rest of Firehouse 51 looked out at the lake in horror, unable to help.
Chicago Fire airs on NBC and season 10 will begin on 22 September 2021.
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