diff --git a/include/scratchcpp/virtualmachine.h b/include/scratchcpp/virtualmachine.h
index efacb16a..0e262cff 100644
--- a/include/scratchcpp/virtualmachine.h
+++ b/include/scratchcpp/virtualmachine.h
@@ -105,7 +105,11 @@ class LIBSCRATCHCPP_EXPORT VirtualMachine
 
         void setBytecode(unsigned int *code);
 
+        unsigned int **procedures() const;
+        const BlockFunc *functions() const;
         const Value *constValues() const;
+        Value **variables() const;
+        List **lists() const;
 
         unsigned int *bytecode() const;
 
diff --git a/src/engine/script_p.h b/src/engine/script_p.h
index 5a321c6b..9a311eef 100644
--- a/src/engine/script_p.h
+++ b/src/engine/script_p.h
@@ -19,16 +19,16 @@ struct ScriptPrivate
         ScriptPrivate(Target *target, IEngine *engine);
         ScriptPrivate(const ScriptPrivate &) = delete;
 
-        unsigned int *bytecode;
+        unsigned int *bytecode = nullptr;
         std::vector<unsigned int> bytecodeVector;
 
-        Target *target;
-        IEngine *engine;
+        Target *target = nullptr;
+        IEngine *engine = nullptr;
 
         unsigned int **procedures = nullptr;
         std::vector<unsigned int *> proceduresVector;
 
-        BlockFunc *functions;
+        BlockFunc *functions = nullptr;
         std::vector<BlockFunc> functionsVector;
 
         const Value *constValues = nullptr;
diff --git a/src/engine/virtualmachine.cpp b/src/engine/virtualmachine.cpp
index 68b7c945..dc9b3c58 100644
--- a/src/engine/virtualmachine.cpp
+++ b/src/engine/virtualmachine.cpp
@@ -57,12 +57,36 @@ void VirtualMachine::setBytecode(unsigned int *code)
     impl->pos = code;
 }
 
+/*! Returns the array of procedures. */
+unsigned int **VirtualMachine::procedures() const
+{
+    return impl->procedures;
+}
+
+/*! Returns the array of functions (block implementation function pointers). */
+const BlockFunc *VirtualMachine::functions() const
+{
+    return impl->functions;
+}
+
 /*! Returns the array of constant values. */
 const Value *VirtualMachine::constValues() const
 {
     return impl->constValues;
 }
 
+/*! Returns the array of Value pointers of variables. */
+Value **VirtualMachine::variables() const
+{
+    return impl->variables;
+}
+
+/*! Returns the array of lists. */
+List **VirtualMachine::lists() const
+{
+    return impl->lists;
+}
+
 /*! Returns the bytecode array. */
 unsigned int *VirtualMachine::bytecode() const
 {
diff --git a/src/engine/virtualmachine_p.h b/src/engine/virtualmachine_p.h
index 6d17b163..af00076b 100644
--- a/src/engine/virtualmachine_p.h
+++ b/src/engine/virtualmachine_p.h
@@ -56,7 +56,7 @@ struct VirtualMachinePrivate
         bool updatePos = false;
 
         unsigned int **procedures = nullptr;
-        BlockFunc *functions;
+        BlockFunc *functions = nullptr;
         const Value *constValues = nullptr;
         Value **variables = nullptr;
         List **lists = nullptr;
diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
index 04b734ab..41f75403 100644
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -25,3 +25,4 @@ add_subdirectory(target_interfaces)
 add_subdirectory(blocks)
 add_subdirectory(scratchconfiguration)
 add_subdirectory(assets)
+add_subdirectory(script)
diff --git a/test/script/CMakeLists.txt b/test/script/CMakeLists.txt
new file mode 100644
index 00000000..35186984
--- /dev/null
+++ b/test/script/CMakeLists.txt
@@ -0,0 +1,14 @@
+add_executable(
+  script_test
+  script_test.cpp
+)
+
+target_link_libraries(
+  script_test
+  GTest::gtest_main
+  GTest::gmock_main
+  scratchcpp
+  scratchcpp_mocks
+)
+
+gtest_discover_tests(script_test)
diff --git a/test/script/script_test.cpp b/test/script/script_test.cpp
new file mode 100644
index 00000000..36ac6cc1
--- /dev/null
+++ b/test/script/script_test.cpp
@@ -0,0 +1,84 @@
+#include <scratchcpp/script.h>
+#include <scratchcpp/virtualmachine.h>
+#include <scratchcpp/target.h>
+#include <scratchcpp/list.h>
+#include <enginemock.h>
+
+#include "../common.h"
+
+using namespace libscratchcpp;
+
+class ScriptTest : public testing::Test
+{
+    public:
+        Target m_target;
+        EngineMock m_engine;
+};
+
+TEST_F(ScriptTest, Bytecode)
+{
+    Script script(nullptr, nullptr);
+    ASSERT_EQ(script.bytecode(), nullptr);
+    ASSERT_TRUE(script.bytecodeVector().empty());
+
+    script.setBytecode({ vm::OP_START, vm::OP_HALT });
+    ASSERT_EQ(script.bytecode()[0], vm::OP_START);
+    ASSERT_EQ(script.bytecode()[1], vm::OP_HALT);
+    ASSERT_EQ(script.bytecodeVector(), std::vector<unsigned int>({ vm::OP_START, vm::OP_HALT }));
+}
+
+unsigned int testFunction(VirtualMachine *)
+{
+    return 0;
+}
+
+TEST_F(ScriptTest, Start)
+{
+    static std::vector<unsigned int> bytecode = { vm::OP_START, vm::OP_HALT };
+    static std::vector<unsigned int *> procedures = { bytecode.data() };
+    static std::vector<BlockFunc> functions = { &testFunction };
+    static std::vector<Value> constValues = { "test" };
+
+    std::unique_ptr<Value> var = std::make_unique<Value>();
+    static std::vector<Value *> variables = { var.get() };
+
+    std::unique_ptr<List> list = std::make_unique<List>("", "");
+    static std::vector<List *> lists = { list.get() };
+
+    Script script1(nullptr, nullptr);
+
+    std::shared_ptr<VirtualMachine> vm = script1.start();
+    ASSERT_TRUE(vm);
+    ASSERT_EQ(vm->target(), nullptr);
+    ASSERT_EQ(vm->engine(), nullptr);
+    ASSERT_EQ(vm->bytecode(), nullptr);
+    ASSERT_EQ(vm->procedures(), nullptr);
+    ASSERT_EQ(vm->functions(), nullptr);
+    ASSERT_EQ(vm->constValues(), nullptr);
+    ASSERT_EQ(vm->variables(), nullptr);
+    ASSERT_EQ(vm->lists(), nullptr);
+
+    Script script2(&m_target, &m_engine);
+
+    vm = script2.start();
+    ASSERT_TRUE(vm);
+    ASSERT_EQ(vm->target(), &m_target);
+    ASSERT_EQ(vm->engine(), &m_engine);
+
+    Script script3(&m_target, &m_engine);
+    script3.setBytecode(bytecode);
+    script3.setProcedures(procedures);
+    script3.setFunctions(functions);
+    script3.setConstValues(constValues);
+    script3.setVariables(variables);
+    script3.setLists(lists);
+
+    vm = script3.start();
+    ASSERT_TRUE(vm);
+    ASSERT_EQ(vm->bytecode()[0], bytecode[0]);
+    ASSERT_EQ(vm->procedures()[0], procedures[0]);
+    ASSERT_EQ(vm->functions()[0], functions[0]);
+    ASSERT_EQ(vm->constValues()[0].toString(), constValues[0].toString());
+    ASSERT_EQ(vm->variables()[0], variables[0]);
+    ASSERT_EQ(vm->lists()[0], lists[0]);
+}
diff --git a/test/virtual_machine/virtual_machine_test.cpp b/test/virtual_machine/virtual_machine_test.cpp
index d9a0b027..8de089fd 100644
--- a/test/virtual_machine/virtual_machine_test.cpp
+++ b/test/virtual_machine/virtual_machine_test.cpp
@@ -25,6 +25,17 @@ TEST(VirtualMachineTest, Constructors)
     ASSERT_EQ(vm2.script(), &script);
 }
 
+TEST(VirtualMachineTest, Procedures)
+{
+    static unsigned int procedure[] = { OP_START, OP_HALT };
+    static unsigned int *procedures[] = { procedure };
+
+    VirtualMachine vm;
+    ASSERT_EQ(vm.procedures(), nullptr);
+    vm.setProcedures(procedures);
+    ASSERT_EQ(vm.procedures(), procedures);
+}
+
 TEST(VirtualMachineTest, ConstValues)
 {
     static Value constValues[] = { "test1", "test2" };
@@ -35,6 +46,28 @@ TEST(VirtualMachineTest, ConstValues)
     ASSERT_EQ(vm.constValues(), constValues);
 }
 
+TEST(VirtualMachineTest, Variables)
+{
+    Value var;
+    Value *variables[] = { &var };
+
+    VirtualMachine vm;
+    ASSERT_EQ(vm.variables(), nullptr);
+    vm.setVariables(variables);
+    ASSERT_EQ(vm.variables(), variables);
+}
+
+TEST(VirtualMachineTest, Lists)
+{
+    List list("", "");
+    List *lists[] = { &list };
+
+    VirtualMachine vm;
+    ASSERT_EQ(vm.lists(), nullptr);
+    vm.setLists(lists);
+    ASSERT_EQ(vm.lists(), lists);
+}
+
 TEST(VirtualMachineTest, Bytecode)
 {
     static unsigned int bytecode[] = { OP_START, OP_HALT };
@@ -1240,7 +1273,17 @@ TEST(VirtualMachineTest, OP_EXEC)
     }
 }
 
-TEST(VirtualMachineTest, Procedures)
+TEST(VirtualMachineTest, Functions)
+{
+    static BlockFunc functions[] = { &testFunction1, &testFunction2 };
+
+    VirtualMachine vm;
+    ASSERT_EQ(vm.functions(), nullptr);
+    vm.setFunctions(functions);
+    ASSERT_EQ(vm.functions(), functions);
+}
+
+TEST(VirtualMachineTest, RunProcedures)
 {
     static unsigned int bytecode[] = {
         OP_START, OP_INIT_PROCEDURE, OP_CONST, 0, OP_ADD_ARG, OP_CONST, 1, OP_ADD_ARG, OP_CALL_PROCEDURE, 0, OP_NULL, OP_EXEC, 0, OP_INIT_PROCEDURE, OP_CALL_PROCEDURE, 1, OP_HALT