Chicago Fire fans have been left in shock after the discovery of an old commercial for Google Nests that features Taylor Kinney and Jesse Spencer in character as Kelly Severide and Matthew Casey.
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"Who was gonna tell me this commercial existed?" tweeted one fan, sharing the short commercial which sees Severide watching The Voice while on shift. Casey then walks into the room to suggest it may be "time to break out the holiday decorations".
WATCH: Unearthed Christmas commercial with Chicago Fire's Taylor Kinney and Jesse Spencer
"Way ahead of you, Captain," replies Severide, then asking Google to "turn on the reindeer".
The camera then cuts to the fire trucks covered in Christms lights and flashing reindeer, and the two firefighters wrapping their arms around each other.
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"How did I not know about this??" exclaimed one fan as another called it "t0he best thing I ever seen".
The commercial was from the 2017 holiday season, four years before Jesse decided to bow out of the NBC series after 10 years.
Severide surprised Casey with the decorations in the commercial
Fans saw Casey decide to leave Chicago for three years to move to Oregon and help raise his late best friend's children, with him and girlfriend Sylvie Brett attempting to try long distance.
"For over ten years you made this a special place," viewers saw deputy district commissioner Boden tell Casey at the end of the episode.
"Everyone you worked with on this shift, we got to call you brother. This place will never be the same and I thank you for your kindness, generosity and passion for this job. You will be dearly missed brother."
In the episode, Casey saved best friend Severide's life in his final fire, and Severide was near to tears as he said his goodbyes. Jesse told press that his decision to leave comes after 18 years on network TV; he worked for eight years on NBC show House before helping to launch Chicago Fire.
Casey has left after 10 years
However he hinted that it won't be forever; he is expected to appear for the wedding of Severide and Stella Kidd.
"I think it was pretty organic that he’s leaving and he’s going for three years but is he? We don’t know," he said.
"I realized I’d been doing TV for a long time, so I added it up… We were coming up on the 200th episode and I called Derek to break the news that it was time for me to leave the show.
"He agreed we should at least get Casey to the 200th episode. It was a difficult decision because I’ve loved the show from the start but there are other things I’d like to do in the future. There’s family I need to take care of, and 18 years is a long time."
One Chicago airs Wednesday at 8/7c on NBC
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