Emmy Rossum isn't the only one leaving Shameless this season. In an emotional Instagram post, Cameron Monaghan announced Monday that Sunday's upcoming episode will be his last.

"I have been a series regular on this show for roughly ten years," Monaghan wrote. "I was the tender age of 15 when we shot the pilot, and I came of age in so many ways, both legally and personally. I was very lucky to mature and grow with this show. Experiencing so many firsts, maturing as an actor, a professional, and a human. In the process gaining friends, family, and the best coworkers a very lucky actor could ask for, and for this I can be nothing but gracious. All good things come to an end. An old cliche, but one that rings true with a sincerity and clarity especially in moments like these. Everything ends."

Monaghan says he's known since last year that he'd be ending his journey as Ian Gallagher, but he didn't want to give the game away by announcing it too soon. Instead, he wanted fans to experience all the highs and lows of his final season and his character's journey as they came.

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"This role has been a joy to inhabit, a wild and special ride, and I'd like to thank #Shameless as well as you, the viewers, for being there with him," Monaghan finished. "Goodbye, Ian Clayton Gallagher. We'll meet again?"

Normally, we'd take that last line as an open door for Monaghan to return in future seasons if he chooses to, but with Rossum departing the show after Season 9, we're beginning to wonder if future seasons will even happen. This could be the beginning of the end for Shameless.

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I have been a series regular on this show for roughly ten years. I was the tender age of fifteen when we shot the pilot, and I came of age in so many ways, both legally and personally. I was very lucky to mature and grow with this show. Experiencing so many firsts, maturing as an actor, a professional, and a human. In the process gaining friends, family, and the best coworkers a very lucky actor could ask for, and for this I can be nothing but gracious. All good things come to an end. An old cliche, but one that rings true with a sincerity and clarity especially in moments like these. Everything ends. The next episode will be my last. I have known since last year, but I didn't want to give it away too early as I wanted this season to be a surprise for the audience, allowing them to experience Ian's unsure journey with his character. This role has been a joy to inhabit, a wild and special ride, and I'd like to thank #Shameless as well as you, the viewers, for being there with him. Goodbye, Ian Clayton Gallagher. We'll meet again?

A post shared by Cameron Monaghan (@cameronmonaghan) on

Shameless airs Sundays at 9/8c on Showtime.

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