In a lengthy Instagram post on Thursday, Parsons gushes about the cast, the writers and the fans who made it possible for the sitcom to go on so long in the first place. Alongside a pic of the main cast with a drawn heart encircling them, Parsons took six separate slides to say everything he wanted to say. "❤️Swipe for my caption to this picture which was too long to just write here (not surprising given the circumstances) ❤️," he explains.
"It is hard (nearly impossible, actually) to really accept that this is a picture of the first of the final 24 episodes we will shoot for The Big Bang Theory," the 45-year-old actor writes. "I feel very fortunate that we have another 23 episodes to shoot this season because I am hopeful that with each and every one, my level of REALLY accepting this fact will sink in."
Parsons goes on to describe his deep thanks for the fans of the long-running CBS show.
"Something else I feel grateful for - and this gratitude needs no time to 'sink in' or become more 'realized;' this grateful-feeling is always with me but is multiplied in this moment of us announcing our final season - but I feel such intense gratitude for our devoted viewers who are the ACTUAL reason we have been graced with the opportunity to explore these characters for 12 years of our lives," he says.
The Hidden Figures star also shares his kind words for the show's crew.
"I feel grateful to our crew - many, many of whom have been with us since day one - and who are the people who bring a sense of steadiness and dependability," Parsons expresses. "Who are so warm and kind and always quick to say hello and smile at us every time we come to the set and who, even though you don't see them on TV, are in many ways the real and steady heartbeat that keeps this body of work alive and breathing while we, like flailing arms and legs, act like jackasses and fools in attempt to make someone laugh."
Parsons turns his focus to the writers as well, whom, he says, are responsible for Big Bang Theory existing in the first place.
"I am grateful to all the writers of our show - those with us now and those that have come and gone - because, without them, there would literally be no Big Bang Theory at all, ever," he notes. "The writers thought of this show, the writers created these characters, the writers are the ones who found ways to keep coming up with organic, entertaining ways to keep the life of this show going which a task much, much more challenging than anyone other than them will ever know or understand."
In the final section of the letter, Parsons expresses his gratitude for all those who appeared on the show throughout the years.
"While I know that they already know it, it bears repeating again and again: I am so terribly grateful for the cast members who aren't pictured here - whether they were in one scene or many episodes along the way; you are all my playmates that I have fallen in love with and who have become a part of my life on set and off," he gushes. "You are my playmates when we don't feel like playing but have to because it's out job to get out there and communicate our job to get out there and communicate and pretend we're these other fictional people and we look into each other's eyes and say these words and end up creating this weird, other reality that has enriched my life more than I will fully ever understand."
Parsons concludes his letter on a melancholy note, writing, "I will miss all of you and all of this more than I can say and more than I can know at this time."
According to Entertainment Weekly, Parsons was "ready to walk away" from the sitcom, after making a reported salary near $1 million per episode. And because the show wouldn't be the same without its lead character, EW reports that the network decided to pull the plug on the longest-running multi-camera series in TV history.
ET has reached out to CBS, Warner Bros. and Parsons' rep regarding the report that the show is ending because he wanted it to. Parsons' rep had no comment.
The final episode of The Big Bang Theory will air in May 2019. Watch the video below for more on the show's final season: