IIRC (it’s been decades since I’ve read it) they each pop like 4 pills before waiting to hear how they work (his grandparents are kind of stupid.) Each pill subtracts 20 years, so they all lose 80 years. And one of Charlie’s grandparents is like 78 or 79 so they disappear while the rest are over 80 and go back to being babies/toddlers.
So Charlie takes the elevator down to Minusland, which is a bit like the Upside Down from Stranger Things, and goes on an adventure to bring his grandparent back.
IIRC (it’s been decades since I’ve read it) they each pop like 4 pills before waiting to hear how they work (his grandparents are kind of stupid.) Each pill subtracts 20 years, so they all lose 80 years. And one of Charlie’s grandparents is like 78 or 79 so they disappear while the rest are over 80 and go back to being babies/toddlers.
So Charlie takes the elevator down to Minusland, which is a bit like the Upside Down from Stranger Things, and goes on an adventure to bring his grandparent back.