diff --git a/src/edit.c b/src/edit.c
index a2a004c..3fa95cd 100644
--- a/src/edit.c
+++ b/src/edit.c
@@ -3022,7 +3022,7 @@
 	return NULL;
 
     if (insert.length > 0 && s[insert.length - 1] == ESC)	// remove trailing ESC
-	s[insert.length - 1] = NUL;
+	s[--insert.length] = NUL;
     return s;
 }