In Side Effects, she has this conversation with Grandpa Max:
Gwen: Let me guess, you learned about nuclear reactors from a monk in China.
Grandpa Max: I picked it up from a monk in Guangdong, China.
Ben still has no clue! Then this guy shows up:
Grandpa Max knows him and all Ben can say is:
You know this guy?
More hints that Grandpa wasn't a plumber of the usual type:
From Ben 10 Facts:
"In the first episode 'And Then There Were 10' what indication was there that Max knew about aliens?
He corrected Gwen that Heatblast was an alien, not a monster"
#Season1Over #Season2Begins #Ben10 #GwenTooSmart