my @LoL = ();      # empty array
$LoL[0] = [];      # ref to anonymous array
$LoL[0]->[0] = []; # another ref to anonymous array

# the hard way
${${$LoL[0]}[0]}[0] = 'Look, up in the sky!';
# the easy way
$LoL[0]->[0]->[1]   = 'It's a bird, it's a plane, it's...';
# the shortcut
$LoL[0]->[0][2]     = 'Superman!';