diff --git a/src/sequence_diagram/model/diagram.cc b/src/sequence_diagram/model/diagram.cc
index 434a7538..5e691f47 100644
--- a/src/sequence_diagram/model/diagram.cc
+++ b/src/sequence_diagram/model/diagram.cc
@@ -497,18 +497,18 @@ bool diagram::inline_lambda_operator_call(const common::id_t id,
             get_participant<model::class_>(parent_class_id);
 
         if (maybe_parent_class && maybe_parent_class.value().is_lambda()) {
-            // auto new_message{m};
-            // new_message.set_
-            auto lambda_operator_activity = get_activity(m.to());
+            if (has_activity(m.to())) {
+                auto lambda_operator_activity = get_activity(m.to());
 
-            // For each call in that lambda activity - reattach this
-            // call to the current activity
-            for (auto &mm : lambda_operator_activity.messages()) {
-                if (!inline_lambda_operator_call(id, new_activity, mm)) {
-                    auto new_message{mm};
+                // For each call in that lambda activity - reattach this
+                // call to the current activity
+                for (auto &mm : lambda_operator_activity.messages()) {
+                    if (!inline_lambda_operator_call(id, new_activity, mm)) {
+                        auto new_message{mm};
 
-                    new_message.set_from(id);
-                    new_activity.add_message(new_message);
+                        new_message.set_from(id);
+                        new_activity.add_message(new_message);
+                    }
                 }
             }
 
diff --git a/tests/t20053/.clang-uml b/tests/t20053/.clang-uml
new file mode 100644
index 00000000..1387e310
--- /dev/null
+++ b/tests/t20053/.clang-uml
@@ -0,0 +1,12 @@
+diagrams:
+  t20053_sequence:
+    type: sequence
+    glob:
+      - t20053.cc
+    include:
+      namespaces:
+        - clanguml::t20053
+    using_namespace: clanguml::t20053
+    inline_lambda_messages: true
+    from:
+      - function: "clanguml::t20053::tmain()"
\ No newline at end of file
diff --git a/tests/t20053/t20053.cc b/tests/t20053/t20053.cc
new file mode 100644
index 00000000..03b1c39a
--- /dev/null
+++ b/tests/t20053/t20053.cc
@@ -0,0 +1,28 @@
+namespace clanguml {
+namespace t20053 {
+template <typename F> int a1(F &&f) { return f(42); }
+
+int a2(int x) { return 2; }
+
+int a3(int x) { return 3; }
+
+int tmain()
+{
+    // Call expression in a nested lambda
+    auto v1 = [](auto &&arg1) {
+        return [](auto &&arg2) { return a2(arg2); }(arg1);
+    }(0);
+
+    // Nested lambda call without any actual calls
+    auto v2 = [](auto &&arg1) {
+        return [](auto &&arg2) { return arg2 + 2; }(arg1);
+    }(0);
+
+    // Call expression in a nested lambda in call expression
+    auto v4 = a1(
+        [](auto &&arg1) { return [](auto &&arg2) { return a3(arg2); }(arg1); });
+
+    return 0;
+}
+}
+}
\ No newline at end of file
diff --git a/tests/t20053/test_case.h b/tests/t20053/test_case.h
new file mode 100644
index 00000000..29dab3e6
--- /dev/null
+++ b/tests/t20053/test_case.h
@@ -0,0 +1,70 @@
+/**
+ * tests/t20053/test_case.h
+ *
+ * Copyright (c) 2021-2024 Bartek Kryza <bkryza@gmail.com>
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+TEST_CASE("t20053", "[test-case][sequence]")
+{
+    auto [config, db] = load_config("t20053");
+
+    auto diagram = config.diagrams["t20053_sequence"];
+
+    REQUIRE(diagram->name == "t20053_sequence");
+
+    auto model = generate_sequence_diagram(*db, diagram);
+
+    REQUIRE(model->name() == "t20053_sequence");
+
+    {
+        auto src = generate_sequence_puml(diagram, *model);
+        AliasMatcher _A(src);
+
+        REQUIRE_THAT(src, StartsWith("@startuml"));
+        REQUIRE_THAT(src, EndsWith("@enduml\n"));
+
+        REQUIRE_THAT(src, HasCall(_A("tmain()"), _A("a2(int)"), ""));
+
+        REQUIRE_THAT(src,
+            HasCall(_A("tmain()"),
+                _A("a1<(lambda at t20053.cc:23:9)>((lambda at t20053.cc:23:9) "
+                   "&&)"),
+                ""));
+
+        REQUIRE_THAT(src,
+            HasCall(_A("a1<(lambda at t20053.cc:23:9)>((lambda at "
+                       "t20053.cc:23:9) &&)"),
+                _A("a3(int)"), ""));
+
+        save_puml(config.output_directory(), diagram->name + ".puml", src);
+    }
+
+    {
+        auto j = generate_sequence_json(diagram, *model);
+
+        using namespace json;
+
+        save_json(config.output_directory(), diagram->name + ".json", j);
+    }
+
+    {
+        auto src = generate_sequence_mermaid(diagram, *model);
+
+        mermaid::AliasMatcher _A(src);
+        using mermaid::IsClass;
+
+        save_mermaid(config.output_directory(), diagram->name + ".mmd", src);
+    }
+}
\ No newline at end of file
diff --git a/tests/test_cases.cc b/tests/test_cases.cc
index 80ea3778..524f994e 100644
--- a/tests/test_cases.cc
+++ b/tests/test_cases.cc
@@ -481,6 +481,7 @@ using namespace clanguml::test::matchers;
 #include "t20051/test_case.h"
 #endif
 #include "t20052/test_case.h"
+#include "t20053/test_case.h"
 
 ///
 /// Package diagram tests
diff --git a/tests/test_cases.yaml b/tests/test_cases.yaml
index 9e61d031..573e6998 100644
--- a/tests/test_cases.yaml
+++ b/tests/test_cases.yaml
@@ -377,7 +377,10 @@ test_cases:
       title: Test case for CUDA calls callee_type filter
       description:
     - name: t20052
-      title: Test case for CUDA calls callee_type filter
+      title: Test case for inlining lambda operator calls
+      description:
+    - name: t20053
+      title: Test case for inlining nested lambda operator calls
       description:
   Package diagrams:
     - name: t30001