diff --git a/deps/v8/include/v8-version.h b/deps/v8/include/v8-version.h
index 3d41a2cb3f..1c3e60f95e 100644
--- a/deps/v8/include/v8-version.h
+++ b/deps/v8/include/v8-version.h
@@ -11,7 +11,7 @@
 #define V8_MAJOR_VERSION 5
 #define V8_MINOR_VERSION 0
 #define V8_BUILD_NUMBER 71
-#define V8_PATCH_LEVEL 32
+#define V8_PATCH_LEVEL 33
 
 // Use 1 for candidates and 0 otherwise.
 // (Boolean macro values are not supported by all preprocessors.)
diff --git a/deps/v8/src/regexp/regexp-parser.cc b/deps/v8/src/regexp/regexp-parser.cc
index 2fe6fde82a..46c593c264 100644
--- a/deps/v8/src/regexp/regexp-parser.cc
+++ b/deps/v8/src/regexp/regexp-parser.cc
@@ -358,13 +358,17 @@ RegExpTree* RegExpParser::ParseDisjunction() {
             uc32 p = Next();
             Advance(2);
             if (unicode()) {
-              ZoneList<CharacterRange>* ranges = ParsePropertyClass();
-              if (ranges == nullptr) {
-                return ReportError(CStrVector("Invalid property name"));
+              if (FLAG_harmony_regexp_property) {
+                ZoneList<CharacterRange>* ranges = ParsePropertyClass();
+                if (ranges == nullptr) {
+                  return ReportError(CStrVector("Invalid property name"));
+                }
+                RegExpCharacterClass* cc =
+                    new (zone()) RegExpCharacterClass(ranges, p == 'P');
+                builder->AddCharacterClass(cc);
+              } else {
+                return ReportError(CStrVector("Invalid escape"));
               }
-              RegExpCharacterClass* cc =
-                  new (zone()) RegExpCharacterClass(ranges, p == 'P');
-              builder->AddCharacterClass(cc);
             } else {
               builder->AddCharacter(p);
             }