Swear

The previously mentioned USC Drama production of Fortinbras included a Hamlet played by someone who had notable resemblance to Dante from Clerks. Took a few days more to realize another resemblance...

That play is a comedy about possible events in the aftermath of The Tragedy of Hamlet, the Prince of Denmark. Young Fortinbras shows up at the Danish court moments after Hamlet, Laertes, Claudius and Gertrude have all killed each other. This places him in a fortunate position to gain the crown - not that it does him any good, considering he ends up dealing with ghosts who are no more rational in death than they were in life.

Clerks, meanwhile,  begins with a young man, Dante Hicks, answering an early morning phone call from his employer, asking him to work the morning shift at the Quick Stop, a convenience store. Dante is not interested: He closed the previous night, has had minimal sleep as a result, and had plans for a hockey game that afternoon. He is eventually convinced, but only after demanding "Swear. Swear you'll be in by twelve [i.e. noon]."

"Swear," of course, is what the Ghost of Old Hamlet demands, as well, atop the battlements of Elsinore. He is throwing his own support behind Young Hamlet's desire for secrecy. Three times, he repeats "SWEAR!" in bone-chilling chain-rattling THX sound. When Hamlet himself is a ghost in "Fortinbras" - trapped in a television set, not that he knows what it is - these are his first words as well. "Swear! Swear! Swear!.....that you won't touch that button [the on-off switch.]"

(Spoiler alert: Both are ultimately disappointed. Dante's boss, like Godot, never shows up, while Ophelia's ghost finds a remote control and turns off the television.)