Did you see that guy going down the residential area at 110 mph? He went through someones fucking lawn, THEIR GODDAMN LAWN AND THROUGH THE FENCE TOO. God, then he got to the orphanage, it was a massacre. I tell ya man, he was going ape shit.
Someone who goes completely "Ape Shit" over something means that someone goes completely crazy over this object, person, place or thing.
"Dude, did you SEE that?" said Brooke.
"No, what was it that you saw?" replied Brian.
"The Famous Butter just went completely APE SHITon the mic!" said Brooke.