Grim Adventures - Time Reverses [HD]

From The Grim Adventures of Billy & Mandy Season 1 Episode 17c: "The Halls of Time"

Grim: "I hope you learned a lesson, Billy"
[Billy and Irwin turn into infants]
Grim: "Ay, chihuahua! Mandy?"
Mandy: "Do you think maybe those dopes put the hourglasses back upside down?" [turns into an infant] "We gotta go back and put them right-side up before we disappear completely" [sucks thumb]
Grim: "Disappear? Completely?" [laughs maniacally, ages backwards]
Grim: "You gotta take us back. Time is reversing itself!"
Father Time: "Welcome to the Halls of-- say, haven't I seen you before?"
Grim: "The hourglasses were put back upside down. We've got to go turn them back bef--"
Father Time: "No way, José! I remember you whippersnappers, and you can just high-tail it out of here!"
[Grim steals Father Time's scythe]
Mandy: "Hurry, Grim!"
[Grim rides the scythe to their hourglasses]
Mandy: "Stop! There Irwin's"
[Irwin's hourglass runs out of sand]
Mandy: "Irwin!"
[Irwin poofs out of existence]
Mandy: "Billy's!"
[Billy's hourglass runs out of sand, all age backwards, Billy poofs out of existence]
Mandy: "It's just you and me now, Grim. Hurry, Grim"
[Grim lets Mandy's hourglass run out of sand]
Mandy: "Grim, what do you think you're doing? Why, you no good pile of--" [poofs out of existence]
Grim: [laughs, then continues aging backwards. Fails to budge his hourglass, then poofs out of existence]