advanced_subject attempts to cut out having to explicitly write the subject of your example group when trying to call methods or add arguments to methods. It works by reading the conventional description syntax to determine what the method you are calling is and later you state what you are passing to it. Given you have a file advanced_subject_spec.rb. ```ruby describe Hash do when_initialized_with [:a, :b] do it { should eq({a: :b}) } describe '#fetch' do when_passed :a do it { should eq(:b) } end end end end ``` When you run `rspec -f d advanced_subject_spec.rb` it will output: ``` Hash when initialized with [:a, :b] should eq {:a => :b} #fetch when passed :a should eq :b ```