October 23, 1989: a certain lasagna-loving cat wakes up to find himself alone... Utterly alone.
From the Wikipedia entry:
One storyline, which lasted a week from October 23, 1989 (possibly to coincide with Halloween, although the 31st actually fell the following week), is unique in that it is not humorous. It depicts Garfield awakening in a future in which the house is abandoned and he no longer exists. This is revealed to have been a dream of some kind, and ends with this narration: "An imagination is a powerful tool. It can tint memories of the past, shade perceptions of the present, or paint a future so vivid that it can entice...or terrify, all depending on how we conduct ourselves today." Alternatively, some theorize that the end of this storyline actually implies that the rest of the series, the more conventional strips, are all fantasies Garfield is playing out in his head to delude himself from realizing the dark turn his life has taken, as he slowly starves to death in an abandoned house. This is arguably supported by the text, as the narration reads "After years of taking life for granted, Garfield is shaken by a horrifying vision of the inevitable process called 'time'. He has only one weapon... Denial" right before Jon and Odie reappear. This emphasis on Denial, with the word given its own box in the panel it appears in, and being followed immediately by the earlier text on the power of the imagination, could support the theory. However, it could also be that denial is what Garfield needed to snap himself out of this dark vision.Is it a coincidence that this storyline started exactly 11 years after the first appearence of Pooky? I think not. Sorry if this episode is common knowledge, but it's new to me.