diff --git a/daos/thread.php b/daos/thread.php
index 2eecbba..9f7ecb7 100644
--- a/daos/thread.php
+++ b/daos/thread.php
@@ -53,11 +53,10 @@ Thread
 
   public static function
   find (
-      int $id)
-  : \Dto\Thread
+      SQLite3 $db,
+      int     $id)
+  : ?\Dto\Thread
   {
-    // TODO: 書くこと
-
     $sql = "
         SELECT
           t.id,
@@ -78,6 +77,19 @@ Thread
           latest DESC";
 
     $result = $db -> query ($sql);
+    $row = $result -> fetchArray (SQLITE3_ASSOC);
+
+    if ($row === false)
+      return null;
+
+    $thread = new \Dto\Thread;
+
+    $thread -> id = $row['id'];
+    $thread -> title = $row['title'];
+    $thread -> explain = $row['explain'];
+    $thread -> length = $row['length'];
+
+    return $thread;
   }
 
 
diff --git a/www/index.php b/www/index.php
index f83c3d8..4ff9194 100644
--- a/www/index.php
+++ b/www/index.php
@@ -5,6 +5,8 @@ require_once __DIR__ . '/../import.php';
 use \Dto;
 
 
+$db = new SQLite3 ('../db.sqlite3');
+
 if (isset ($_GET['page']))
   $page = $_GET['page'];
 else
@@ -29,7 +31,7 @@ else
 $dir = './images/';
 $handle = opendir ($dir);
 
-if ($row = \Dao\Thread :: find ($thread))
+if ($row = \Dao\Thread :: find ($db, $thread))
   {
     $title = $row -> title;
     $explain = $row -> explain;
@@ -39,13 +41,13 @@ if (isset ($_GET['id']))
   {
     if (($_GET['evaluate'] ?? '') === 'good')
       {
-        \Dao\Response :: like ((int) $_GET['id']);
+        \Dao\Response :: like ($db, (int) $_GET['id']);
         header ("Location: ./?thread=$thread&sort=$sort");
       }
 
     if (($_GET['evaluate'] ?? '') === 'bad')
       {
-        \Dao\Response :: dislike ((int) $_GET['id']);
+        \Dao\Response :: dislike ($db, (int) $_GET['id']);
         header ("Location: ./?thread=$thread&sort=$sort");
       }
   }