Chicago Fire's Kara Killmer is set to exit the drama series, after appearing in over 190 episodes.
Killmer has portrayed paramedic Sylvie Brett since season 3 in 2014, and has also made appearances in spin-offs Chicago Med and Chicago PD.
Following the news of her exit, Killmer seemingly confirmed her departure in a post to her Instagram.
"These are the very first few pictures I took, or was tagged in, when I first came to Chicago," she captioned a carousel of images.
Killmer added: "Going up in the Squad 1 basket was my first exposure to the CFD — some of the best firefighters in the country! The view from my very first apartment was absolutely stunning and the beginning of a love affair with the gorgeous city of Chicago!"
In the 10th season of Chicago Fire, Jesse Spencer, who portrayed Sylvie's love interest Matthew Casey, left the show after his character moved to Oregon.
They began a long distance relationship, but in the season 11 finale, Matthew returns to propose to Sylvie.
Could a wedding be on the cards of Sylvie and Matthew?
It is not yet known how many episodes Killmer will appear in of season 12, or how her character will leave the series.
Chicago Fire is available to watch on Sky and NOW in the UK.
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