diff --git a/lib/pigeon/lexer.rb b/lib/pigeon/lexer.rb
index d8001b9..7753ff9 100644
--- a/lib/pigeon/lexer.rb
+++ b/lib/pigeon/lexer.rb
@@ -14,10 +14,12 @@ module Pigeon
       @tokens = []
       @state = HEADER
       @last_good = :START
+      @loops = 0
     end
 
     def tokenize
       until scanner.eos?
+        safety_check
         case @state
         when HEADER then do_header
         when BODY then do_body
@@ -30,6 +32,7 @@ module Pigeon
 
     def tokenize_unsigned(signature)
       until scanner.eos?
+        safety_check
         case @state
         when HEADER then do_header
         when BODY then do_body
@@ -42,6 +45,14 @@ module Pigeon
 
     private
 
+    def safety_check
+      if @loops > 1000
+        raise "RUNAWAY LOOP DETECTED"
+      else
+        @loops += 1
+      end
+    end
+
     attr_reader :bundle_string, :scanner, :tokens
     # TODO: Change all the `{40,90}` values in ::Lexer to real values
     # TODO: Create regexes using string and Regexp.new() for cleaner regexes.
@@ -167,6 +178,7 @@ module Pigeon
         @state = HEADER
         maybe_end_message!
         @last_good = :FOOTER_SEPERATOR
+        @loops = 0
         return
       end
 
diff --git a/spec/pigeon/message_spec.rb b/spec/pigeon/message_spec.rb
index 392c135..bf03cfd 100644
--- a/spec/pigeon/message_spec.rb
+++ b/spec/pigeon/message_spec.rb
@@ -167,14 +167,13 @@ RSpec.describe Pigeon::Message do
   # This was originally a bug nooted during development
   # That caused a runaway loop in the tokenizer.
   it "handles this key: '\\nVUx0hC3'" do
-    pending("Known bug- will fix after writing docs.")
     db.delete_current_draft
     db.new_draft(kind: "unit_test")
     db.update_draft("\nVUx0hC3", "n")
     db.update_draft("n", "\nVUx0hC3")
     Timeout::timeout(0.5) do
       boom = -> { Pigeon::Lexer.tokenize(db.publish_draft.render) }
-      expect(boom).to raise_error(Pigeon::Lexer::LexError)
+      expect(boom).to raise_error("RUNAWAY LOOP DETECTED")
     end
   end