diff --git a/hibernate-core/src/test/java/org/hibernate/orm/test/sql/hand/Speech.java b/hibernate-core/src/test/java/org/hibernate/orm/test/sql/hand/Speech.java
index 1b08f7a20498..1ea236ee6dec 100644
--- a/hibernate-core/src/test/java/org/hibernate/orm/test/sql/hand/Speech.java
+++ b/hibernate-core/src/test/java/org/hibernate/orm/test/sql/hand/Speech.java
@@ -5,34 +5,46 @@
 package org.hibernate.orm.test.sql.hand;
 
 
+import jakarta.persistence.Entity;
+import jakarta.persistence.GeneratedValue;
+import jakarta.persistence.Id;
+
 /**
  * @author Emmanuel Bernard
  */
-public class Speech {
+@Entity
+public class Speech implements SpeechInterface {
+	@Id @GeneratedValue
 	private Integer id;
 	private String name;
 	private Double length;
 
+	@Override
 	public Integer getId() {
 		return id;
 	}
 
+	@Override
 	public void setId(Integer id) {
 		this.id = id;
 	}
 
+	@Override
 	public Double getLength() {
 		return length;
 	}
 
+	@Override
 	public void setLength(Double length) {
 		this.length = length;
 	}
 
+	@Override
 	public String getName() {
 		return name;
 	}
 
+	@Override
 	public void setName(String name) {
 		this.name = name;
 	}
diff --git a/hibernate-core/src/test/java/org/hibernate/orm/test/sql/hand/SpeechInterface.java b/hibernate-core/src/test/java/org/hibernate/orm/test/sql/hand/SpeechInterface.java
new file mode 100644
index 000000000000..c23829854582
--- /dev/null
+++ b/hibernate-core/src/test/java/org/hibernate/orm/test/sql/hand/SpeechInterface.java
@@ -0,0 +1,19 @@
+/*
+ * SPDX-License-Identifier: LGPL-2.1-or-later
+ * Copyright Red Hat Inc. and Hibernate Authors
+ */
+package org.hibernate.orm.test.sql.hand;
+
+/**
+ * @author Steve Ebersole
+ */
+public interface SpeechInterface {
+	Integer getId();
+	void setId(Integer id);
+
+	Double getLength();
+	void setLength(Double length);
+
+	String getName();
+	void setName(String name);
+}
diff --git a/hibernate-core/src/test/java/org/hibernate/orm/test/sql/hand/query/EntityReturnClassTests.java b/hibernate-core/src/test/java/org/hibernate/orm/test/sql/hand/query/EntityReturnClassTests.java
new file mode 100644
index 000000000000..88f8c47a6141
--- /dev/null
+++ b/hibernate-core/src/test/java/org/hibernate/orm/test/sql/hand/query/EntityReturnClassTests.java
@@ -0,0 +1,131 @@
+/*
+ * SPDX-License-Identifier: LGPL-2.1-or-later
+ * Copyright Red Hat Inc. and Hibernate Authors
+ */
+package org.hibernate.orm.test.sql.hand.query;
+
+import org.hibernate.orm.test.sql.hand.Speech;
+import org.hibernate.orm.test.sql.hand.SpeechInterface;
+import org.hibernate.query.NativeQuery;
+import org.hibernate.testing.orm.junit.DomainModel;
+import org.hibernate.testing.orm.junit.Jira;
+import org.hibernate.testing.orm.junit.JiraKey;
+import org.hibernate.testing.orm.junit.NotImplementedYet;
+import org.hibernate.testing.orm.junit.SessionFactory;
+import org.hibernate.testing.orm.junit.SessionFactoryScope;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+import java.util.List;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+/**
+ * @author Steve Ebersole
+ */
+@SuppressWarnings("JUnitMalformedDeclaration")
+@DomainModel(annotatedClasses = {SpeechInterface.class, Speech.class})
+@SessionFactory
+@Jira("https://hibernate.atlassian.net/browse/HHH-18864")
+public class EntityReturnClassTests {
+
+	// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+	// no return-class -> no problem
+
+	@Test
+	@JiraKey("HHH-18864")
+	public void testAddEntityNoReturn(SessionFactoryScope scope) {
+		scope.inTransaction( (session) -> {
+			//noinspection unchecked,deprecation
+			NativeQuery<Speech> query = session.createNativeQuery( "select {s.*} from Speech s" );
+			query.addEntity("s", Speech.class);
+			List<Speech> l = query.list();
+			assertEquals( l.size(), 1 );
+		} );
+	}
+
+	@Test
+	@JiraKey("HHH-18864")
+	public void testAddRootNoReturn(SessionFactoryScope scope) {
+		scope.inTransaction( (session) -> {
+			//noinspection unchecked,deprecation
+			NativeQuery<Speech> query = session.createNativeQuery( "select {s.*} from Speech s" );
+			query.addRoot("s", Speech.class);
+			List<Speech> l = query.list();
+			assertEquals( l.size(), 1 );
+		} );
+	}
+
+
+	// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+	// entity return-class -> problems with 2 `ResultBuilder` refs
+
+	@Test
+	@JiraKey("HHH-18864")
+	@NotImplementedYet
+	public void testAddEntityWithEntityReturn(SessionFactoryScope scope) {
+		scope.inTransaction( (session) -> {
+			NativeQuery<Speech> query = session.createNativeQuery( "select {s.*} from Speech s", Speech.class );
+			query.addEntity("s", Speech.class);
+			List<Speech> l = query.list();
+			assertEquals( l.size(), 1 );
+		} );
+	}
+
+	@Test
+	@JiraKey("HHH-18864")
+	@NotImplementedYet
+	public void testAddRootWithEntityReturn(SessionFactoryScope scope) {
+		scope.inTransaction( (session) -> {
+			NativeQuery<Speech> query = session.createNativeQuery( "select {s.*} from Speech s", Speech.class );
+			query.addRoot("s", Speech.class);
+			List<Speech> l = query.list();
+			assertEquals( l.size(), 1 );
+		} );
+	}
+
+
+	// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+	// entity-interface return-class -> problems with `JdbcType` determination
+
+	@Test
+	@JiraKey("HHH-18864")
+	@NotImplementedYet
+	public void testAddEntityWithInterfaceReturn(SessionFactoryScope scope) {
+		scope.inTransaction( (session) -> {
+			NativeQuery<SpeechInterface> query = session.createNativeQuery( "select {s.*} from Speech s", SpeechInterface.class );
+			query.addEntity("s", Speech.class);
+			List<SpeechInterface> l = query.list();
+			assertEquals( l.size(), 1 );
+		} );
+	}
+
+	@Test
+	@JiraKey("HHH-18864")
+	@NotImplementedYet
+	public void testAddRootWithInterfaceReturn(SessionFactoryScope scope) {
+		scope.inTransaction( (session) -> {
+			NativeQuery<SpeechInterface> query = session.createNativeQuery( "select {s.*} from Speech s", SpeechInterface.class );
+			query.addRoot("s", Speech.class);
+			List<SpeechInterface> l = query.list();
+			assertEquals( l.size(), 1 );
+		} );
+	}
+
+
+	@BeforeEach
+	void prepareTestData(SessionFactoryScope scope) {
+		scope.inTransaction( (session) -> {
+			Speech speech = new Speech();
+			speech.setLength( 23d );
+			speech.setName( "Mine" );
+			session.persist( speech );
+		} );
+	}
+
+	@AfterEach
+	void dropTestData(SessionFactoryScope scope) {
+		scope.inTransaction( (session) -> session.createMutationQuery( "delete Speech" ).executeUpdate() );
+	}
+}