diff --git a/libraries/animation/src/AnimExpression.cpp b/libraries/animation/src/AnimExpression.cpp
index 5fc1bc9b4f..79004a72a6 100644
--- a/libraries/animation/src/AnimExpression.cpp
+++ b/libraries/animation/src/AnimExpression.cpp
@@ -208,9 +208,11 @@ AnimExpression::Token AnimExpression::consumeNot(const QString& str, QString::co
 Expr   → Term Expr'
 Expr'  → '||' Term Expr'
        | ε
-Term   → Factor Term'
-Term'  → '&&' Term'
+Term   → Unary Term'
+Term'  → '&&' Unary Term'
        | ε
+Unary  → '!' Unary
+       | Factor
 Factor → INT
        | BOOL
        | FLOAT
@@ -249,9 +251,9 @@ bool AnimExpression::parseExprPrime(const QString& str, QString::const_iterator&
     }
 }
 
-// Term → Factor Term'
+// Term → Unary Term'
 bool AnimExpression::parseTerm(const QString& str, QString::const_iterator& iter) {
-    if (!parseFactor(str, iter)) {
+    if (!parseUnary(str, iter)) {
         return false;
     }
     if (!parseTermPrime(str, iter)) {
@@ -260,11 +262,11 @@ bool AnimExpression::parseTerm(const QString& str, QString::const_iterator& iter
     return true;
 }
 
-// Term'  → '&&' Term' | ε
+// Term' → '&&' Unary Term' | ε
 bool AnimExpression::parseTermPrime(const QString& str, QString::const_iterator& iter) {
     auto token = consumeToken(str, iter);
     if (token.type == Token::And) {
-        if (!parseTerm(str, iter)) {
+        if (!parseUnary(str, iter)) {
             unconsumeToken(token);
             return false;
         }
@@ -280,6 +282,24 @@ bool AnimExpression::parseTermPrime(const QString& str, QString::const_iterator&
     }
 }
 
+// Unary → '!' Unary | Factor
+bool AnimExpression::parseUnary(const QString& str, QString::const_iterator& iter) {
+
+    auto token = consumeToken(str, iter);
+    if (token.type == Token::Not) {
+        if (!parseUnary(str, iter)) {
+            unconsumeToken(token);
+            return false;
+        }
+        _opCodes.push_back(OpCode {OpCode::Not});
+        return true;
+    }
+    unconsumeToken(token);
+
+    return parseFactor(str, iter);
+}
+
+
 // Factor → INT | BOOL | FLOAT | IDENTIFIER | '(' Expr ')'
 bool AnimExpression::parseFactor(const QString& str, QString::const_iterator& iter) {
     auto token = consumeToken(str, iter);
diff --git a/libraries/animation/src/AnimExpression.h b/libraries/animation/src/AnimExpression.h
index 8a1961b326..468217f5b3 100644
--- a/libraries/animation/src/AnimExpression.h
+++ b/libraries/animation/src/AnimExpression.h
@@ -119,6 +119,7 @@ protected:
     bool parseExprPrime(const QString& str, QString::const_iterator& iter);
     bool parseTerm(const QString& str, QString::const_iterator& iter);
     bool parseTermPrime(const QString& str, QString::const_iterator& iter);
+    bool parseUnary(const QString& str, QString::const_iterator& iter);
     bool parseFactor(const QString& str, QString::const_iterator& iter);
 
     OpCode evaluate(const AnimVariantMap& map) const;
diff --git a/tests/animation/src/AnimTests.cpp b/tests/animation/src/AnimTests.cpp
index 63eb39dc48..6812bb63b6 100644
--- a/tests/animation/src/AnimTests.cpp
+++ b/tests/animation/src/AnimTests.cpp
@@ -522,43 +522,19 @@ void AnimTests::testExpressionParser() {
         QVERIFY(e._opCodes[4].type == AnimExpression::OpCode::And);
     }
 
-    /*
-    e = AnimExpression("2 + 3");
-    QVERIFY(e._opCodes.size() == 3);
-    if (e._opCodes.size() == 3) {
-        QVERIFY(e._opCodes[0].type == AnimExpression::OpCode::Int);
-        QVERIFY(e._opCodes[0].intVal == 2);
-        QVERIFY(e._opCodes[1].type == AnimExpression::OpCode::Int);
-        QVERIFY(e._opCodes[1].intVal == 3);
-        QVERIFY(e._opCodes[2].type == AnimExpression::OpCode::Add);
+    e = AnimExpression("!(true || false) && true");
+    QVERIFY(e._opCodes.size() == 6);
+    if (e._opCodes.size() == 6) {
+        QVERIFY(e._opCodes[0].type == AnimExpression::OpCode::Bool);
+        QVERIFY(e._opCodes[0].intVal == (int)true);
+        QVERIFY(e._opCodes[1].type == AnimExpression::OpCode::Bool);
+        QVERIFY(e._opCodes[1].intVal == (int)false);
+        QVERIFY(e._opCodes[2].type == AnimExpression::OpCode::Or);
+        QVERIFY(e._opCodes[3].type == AnimExpression::OpCode::Not);
+        QVERIFY(e._opCodes[4].type == AnimExpression::OpCode::Bool);
+        QVERIFY(e._opCodes[4].intVal == (int)true);
+        QVERIFY(e._opCodes[5].type == AnimExpression::OpCode::And);
     }
-
-    e = AnimExpression("2 + 3 * 10");
-    QVERIFY(e._opCodes.size() == 5);
-    if (e._opCodes.size() == 5) {
-        QVERIFY(e._opCodes[0].type == AnimExpression::OpCode::Int);
-        QVERIFY(e._opCodes[0].intVal == 2);
-        QVERIFY(e._opCodes[1].type == AnimExpression::OpCode::Int);
-        QVERIFY(e._opCodes[1].intVal == 3);
-        QVERIFY(e._opCodes[2].type == AnimExpression::OpCode::Int);
-        QVERIFY(e._opCodes[2].intVal == 10);
-        QVERIFY(e._opCodes[3].type == AnimExpression::OpCode::Multiply);
-        QVERIFY(e._opCodes[4].type == AnimExpression::OpCode::Add);
-    }
-
-    e = AnimExpression("(2 + 3) * 10");
-    QVERIFY(e._opCodes.size() == 5);
-    if (e._opCodes.size() == 5) {
-        QVERIFY(e._opCodes[0].type == AnimExpression::OpCode::Int);
-        QVERIFY(e._opCodes[0].intVal == 2);
-        QVERIFY(e._opCodes[1].type == AnimExpression::OpCode::Int);
-        QVERIFY(e._opCodes[1].intVal == 3);
-        QVERIFY(e._opCodes[2].type == AnimExpression::OpCode::Add);
-        QVERIFY(e._opCodes[3].type == AnimExpression::OpCode::Int);
-        QVERIFY(e._opCodes[3].intVal == 10);
-        QVERIFY(e._opCodes[4].type == AnimExpression::OpCode::Multiply);
-    }
-    */
 }
 
 #define TEST_BOOL_EXPR(EXPR)                                \
@@ -630,23 +606,22 @@ void AnimTests::testExpressionEvaluator() {
     TEST_BOOL_EXPR(f || false);
     TEST_BOOL_EXPR(f || true);
 
-/*
-    result = AnimExpression("(2 + 3) * (5 + 3)").evaluate(vars);
-    QVERIFY(result.type == AnimExpression::OpCode::Int);
-    QVERIFY(result.intVal == (2 + 3) * (5 + 3));
+    TEST_BOOL_EXPR(!true);
+    TEST_BOOL_EXPR(!false);
+    TEST_BOOL_EXPR(!true || true);
 
-    result = AnimExpression("(ten + twenty) * 5").evaluate(vars);
-    QVERIFY(result.type == AnimExpression::OpCode::Int);
-    QVERIFY(result.intVal == (10 + 20) * 5);
+    TEST_BOOL_EXPR(!true && !false || !true);
+    TEST_BOOL_EXPR(!true && !false || true);
+    TEST_BOOL_EXPR(!true && false || !true);
+    TEST_BOOL_EXPR(!true && false || true);
+    TEST_BOOL_EXPR(true && !false || !true);
+    TEST_BOOL_EXPR(true && !false || true);
+    TEST_BOOL_EXPR(true && false || !true);
+    TEST_BOOL_EXPR(true && false || true);
 
-    result = AnimExpression("(ten + twenty) * 5.0").evaluate(vars);
-    QVERIFY(result.type == AnimExpression::OpCode::Float);
-    QVERIFY(result.floatVal == (10 + 20) * 5.0f);
-
-    result = AnimExpression("five * forty").evaluate(vars);
-    QVERIFY(result.type == AnimExpression::OpCode::Float);
-    QVERIFY(result.floatVal == 5.0f * 40.0f);
-*/
+    TEST_BOOL_EXPR(!(true && f) || !t);
+    TEST_BOOL_EXPR(!!!(t) && (!!f || true));
+    TEST_BOOL_EXPR(!(true && f) && true);
 }