This is a satirical take on John Carpenter’s 1982 movie The Thing, which is about an alien creature that hides among the humans by taking on the forms of one person or another. Here, the creature’s shapeshifting in the middle tier of the page is greeted with hilarity instead of horror and the punchline becomes a request to “do [US Secretary of State Alexander] Haig with constipation." 

In other words, this is a very topical one page comic.

(Heavy Metal issue #73, April 1983 – Page 38 The It by Cuti)