DB<23> $hr= { To => [qw/a b c/] }

  DB<24> x %$hr{To}
0  'To'
1  ARRAY(0x55ef21ab6818)
   0  'a'
   1  'b'
   2  'c'
  DB<25> x @$hr{To}              # classic hash slice
0  ARRAY(0x55ef21ab6818)
   0  'a'
   1  'b'
   2  'c'
  DB<26> x @{%$hr{To}}           # only "works" with one hash key 
0  'a'
1  'b'
2  'c'