diff --git a/ReactAndroid/src/main/java/com/facebook/react/cxxbridge/UnpackingJSBundleLoader.java b/ReactAndroid/src/main/java/com/facebook/react/cxxbridge/UnpackingJSBundleLoader.java
index a70f82ada..dd593d010 100644
--- a/ReactAndroid/src/main/java/com/facebook/react/cxxbridge/UnpackingJSBundleLoader.java
+++ b/ReactAndroid/src/main/java/com/facebook/react/cxxbridge/UnpackingJSBundleLoader.java
@@ -72,6 +72,11 @@ public class UnpackingJSBundleLoader extends JSBundleLoader {
   private final boolean mFinishOnBackgroundThread;
   private final @Nullable Runnable mOnUnpackedCallback;
 
+  /**
+   * True if prepare was called.
+   */
+  private boolean mPrepared;
+
   /**
    * Synchronizes unpacking within this process.
    */
@@ -96,13 +101,20 @@ public class UnpackingJSBundleLoader extends JSBundleLoader {
     mFinishOnBackgroundThread = builder.finishOnBackgroundThread;
     mOnUnpackedCallback = builder.callback;
     mFileLocker = null;
+    mPrepared = false;
   }
 
   /**
    * Checks if any file needs to be extracted again, and if so, clears the destination
    * directory and unpacks everything again.
+   *
+   * This method does not do anything if called for the second time
    */
-  /* package */ void prepare() {
+  public synchronized void prepare() {
+    if (mPrepared) {
+      return;
+    }
+
     ReactMarker.logMarker(ReactMarkerConstants.UNPACKER_CHECK_START);
 
     boolean unpacked = false;
@@ -131,6 +143,8 @@ public class UnpackingJSBundleLoader extends JSBundleLoader {
     }
 
     ReactMarker.logMarker(ReactMarkerConstants.UNPACKER_CHECK_END);
+
+    mPrepared = true;
   }
 
   private boolean prepareLocked() throws IOException {