It's still unknown whether or not former star Charlie Sheen will make an appearance in the finale. The actor seemed up for the task when he talked to ET in December, saying, "If they want me there, great. If not, no hard feelings."
Sheen famously exited Two and a Half Menin March 2011 after publicly blasting Lorre. When the show returned that fall, his character, Charlie Harper, had been killed off and Kutcher had joined the cast.
"I don't even think he was invited," Mary Murphy, USC Annenberg School senior lecturer, told ET. "It's like a little kid who says, 'I'm not going!' when he wasn't even asked."
The finale marks a bittersweet end for the cast, but they were quick to remind us that this isn't goodbye forever.
"I'm going to miss all these people a lot," Cryer said. "But it's not like the show will finish and we're all going to die."
Matthew Perry, who returns to television with CBS' The Odd Couple reboot, went through a similar experience with the end of Friends in 2004 and he joked about his experience saying farewell to an iconic TV show.
"It just all ended right there," Perry teased.
The Odd Couple debuts Thursday at 8:30 p.m. ET/PT followed by the one-hour Two and a Half Men series finale at 9 p.m. ET/PT on CBS.