diff --git a/lib/plucky/query.rb b/lib/plucky/query.rb
index c606cda..ee871e7 100755
--- a/lib/plucky/query.rb
+++ b/lib/plucky/query.rb
@@ -87,12 +87,12 @@ def find_one(opts={})
       def find(*ids)
         return nil if ids.empty?
 
-        single_id_find = ids.size == 1 && !ids[0].is_a?(Array)
-
-        if single_id_find
-          first(:_id => ids[0])
+        if ids.size == 1 && !ids.first.is_a?(Enumerable)
+          first(_id: ids.first)
         else
-          all(:_id => ids.flatten)
+          flat_ids = ids.flat_map { |id| Array(id) }.flatten
+
+          all(_id: flat_ids)
         end
       end
 
diff --git a/spec/plucky/query_spec.rb b/spec/plucky/query_spec.rb
index 7a835a7..a024257 100755
--- a/spec/plucky/query_spec.rb
+++ b/spec/plucky/query_spec.rb
@@ -119,6 +119,14 @@
       @query.find('john', 'frank').should == [@john]
     end
 
+    it 'works when passed a set' do
+      @query.find(Set.new(['chris', 'john'])).should == [@chris, @john]
+    end
+
+    it 'a set of one returns an array' do
+      @query.find(Set.new(['chris'])).should == [@chris]
+    end
+
     it "returns nil for nil" do
       @query.find(nil).should be_nil
     end