diff --git a/dfhack/DFHackAPI.cpp b/dfhack/DFHackAPI.cpp
index 7b45b5a17..b023ccbd6 100644
--- a/dfhack/DFHackAPI.cpp
+++ b/dfhack/DFHackAPI.cpp
@@ -113,6 +113,62 @@ bool API::Detach()
     d->p = NULL;
     d->shm_start = 0;
     d->offset_descriptor = NULL;
+    // invalidate all modules
+    if(d->creatures)
+    {
+        delete d->creatures;
+        d->creatures = 0;
+    }
+    if(d->creatures)
+    {
+        delete d->creatures;
+        d->creatures = 0;
+    }
+    if(d->maps)
+    {
+        delete d->maps;
+        d->maps = 0;
+    }
+    if(d->gui)
+    {
+        delete d->gui;
+        d->gui = 0;
+    }
+    if(d->position)
+    {
+        delete d->position;
+        d->position = 0;
+    }
+    if(d->materials)
+    {
+        delete d->materials;
+        d->materials = 0;
+    }
+    if(d->gui)
+    {
+        delete d->gui;
+        d->gui = 0;
+    }
+    if(d->translation)
+    {
+        delete d->translation;
+        d->translation = 0;
+    }
+    if(d->vegetation)
+    {
+        delete d->vegetation;
+        d->vegetation = 0;
+    }
+    if(d->constructions)
+    {
+        delete d->constructions;
+        d->constructions = 0;
+    }
+    if(d->translation)
+    {
+        delete d->translation;
+        d->translation = 0;
+    }
     return true;
 }
 
diff --git a/tools/reveal.cpp b/tools/reveal.cpp
index 127923f43..82da1b2fe 100644
--- a/tools/reveal.cpp
+++ b/tools/reveal.cpp
@@ -85,8 +85,10 @@ int main (void)
     cout << "Press any key to unreveal. Don't close DF or unpause in that case!" << endl;
     cin.ignore();
     cout << "Unrevealing... please wait." << endl;
-    DF.Attach();
     // FIXME: do some consistency checks here!
+    DF.Attach();
+    Maps = DF.getMaps();
+    Maps->Start();
     for(int i = 0; i < hidesaved.size();i++)
     {
         hideblock & hb = hidesaved[i];