diff --git a/rllib/utils/checkpoints.py b/rllib/utils/checkpoints.py
index bb3ce107db9dc..8b9e2d7775f8b 100644
--- a/rllib/utils/checkpoints.py
+++ b/rllib/utils/checkpoints.py
@@ -410,8 +410,22 @@ def from_checkpoint(
         # Get the class constructor to call.
         with open(path / cls.CLASS_AND_CTOR_ARGS_FILE_NAME, "rb") as f:
             ctor_info = pickle.load(f)
+        ctor = ctor_info["class"]
+
+        # Check, whether the constructor actually goes together with `cls`.
+        if not issubclass(ctor, cls):
+            raise ValueError(
+                f"The class ({ctor}) stored in checkpoint ({path}) does not seem to be "
+                f"a subclass of `cls` ({cls})!"
+            )
+        elif not issubclass(ctor, Checkpointable):
+            raise ValueError(
+                f"The class ({ctor}) stored in checkpoint ({path}) does not seem to be "
+                "an implementer of the `Checkpointable` API!"
+            )
+
         # Construct an initial object.
-        obj = ctor_info["class"](
+        obj = ctor(
             *ctor_info["ctor_args_and_kwargs"][0],
             **ctor_info["ctor_args_and_kwargs"][1],
         )