$pinky = {};
# Ooh, you referenced zorch, and it's not there.
$pinky->{zorch} = undef;
# And now you want to reference 'poit' in that as a hash, so we'll add an new anonymous hash instead:
$pinky->{zorch} = {};
$pinky->{zorch}{poit} = undef;
# and then you want to go one more level:
$pinky->{zorch}{poit} = {};
$pinky->{zorch}{poit}{narf} = undef;
# And you want to set that to a value:
$pinky->{zorch}{poit}{narf} = "I don't know, Brain, where will we get hip-waders this time of night?";