diff --git a/brutaldon/threadtree.py b/brutaldon/threadtree.py
index 3c1fdd8..1567f93 100644
--- a/brutaldon/threadtree.py
+++ b/brutaldon/threadtree.py
@@ -1,5 +1,10 @@
 def maketree(descendants):
-    lookup = {(descendant.id, descendant) for descendant in descendants}
+    try:
+        lookup = {(descendant.id, descendant) for descendant in descendants}
+    except:
+        from pprint import pprint
+        pprint(lookup)
+        raise
     replies = {}
     roots = set()
     for descendant in descendants:
diff --git a/brutaldon/views.py b/brutaldon/views.py
index 114fde9..f8f55db 100644
--- a/brutaldon/views.py
+++ b/brutaldon/views.py
@@ -671,7 +671,7 @@ def note(request, next=None, prev=None):
         },
     )
 
-import threadtree
+from . import threadtree
 
 @br_login_required
 def thread(request, id):
@@ -700,7 +700,7 @@ def thread(request, id):
             "context": context,
             "toot": toot,
             "root": root,
-            "posts": threadtree.build(descendants)),
+            "posts": threadtree.build(descendants),
             "own_acct": request.session["active_user"],
             "notifications": notifications,
             "preferences": account.preferences,