diff --git a/action.php b/action.php
new file mode 100644
index 0000000..1413e49
--- /dev/null
+++ b/action.php
@@ -0,0 +1,47 @@
+<?php
+
+if(!defined('DOKU_INC')) die();
+if(!defined('DOKU_PLUGIN')) define('DOKU_PLUGIN', DOKU_INC.'lib/plugins/');
+if(!defined('DOKU_LF')) define('DOKU_LF', "\n");
+
+require_once(DOKU_PLUGIN.'action.php');
+class action_plugin_usetheme extends DokuWiki_Action_Plugin {
+
+    // register hook
+    public function register(Doku_Event_Handler $controller) {
+        $controller->register_hook('DOKUWIKI_STARTED', 'BEFORE', $this, '_handleConf');
+        //$controller->register_hook('MEDIAMANAGER_STARTED', 'BEFORE', $this, '_handleConf');
+        $controller->register_hook('DETAIL_STARTED', 'BEFORE', $this, '_handleConf');
+        //$controller->register_hook('TPL_CONTENT_DISPLAY', 'BEFORE', $this, '_handleContent', array());
+        // only needed for not yet up-to-date templates:
+        $controller->register_hook('DOKUWIKI_STARTED', 'AFTER', $this, '_defineConstants');
+        //$controller->register_hook('MEDIAMANAGER_STARTED', 'AFTER', $this, '_defineConstants');
+        $controller->register_hook('DETAIL_STARTED', 'AFTER', $this, '_defineConstants');
+    }
+
+    public function _defineConstants(Doku_Event $event, $param) {
+        global $conf;
+        // define Template baseURL
+        if(!defined('DOKU_TPL'))
+            define('DOKU_TPL', DOKU_BASE.'lib/tpl/'.$conf['template'].'/');
+
+        // define real Template directory
+        if(!defined('DOKU_TPLINC'))
+            define('DOKU_TPLINC', DOKU_INC.'lib/tpl/'.$conf['template'].'/');
+    }
+
+    public function _handleConf(Doku_Event $event, $param) {
+        global $ID, $ACT, $conf;
+        $dataFile = wikiFN(cleanID($ID));
+        $fp = fopen($dataFile,"r");
+        $firstLine = fgets($fp,512);
+        fclose($fp);
+        preg_match('/~~USETHEME:(.*?)~~/', $firstLine, $match);
+        $template = trim($match[1]);
+        if($template) {
+            $conf['template'] = $template;
+        }
+    }
+}
+
+// vim:ts=4:sw=4:
diff --git a/plugin.info.txt b/plugin.info.txt
new file mode 100644
index 0000000..54c2f90
--- /dev/null
+++ b/plugin.info.txt
@@ -0,0 +1,7 @@
+base usetheme
+author Ruediger Marwein
+email henryxiv@hotmail.com
+date 2021-06-15
+name UseTheme Plugin
+desc Switch Theme using a in-page macro
+url -
diff --git a/syntax.php b/syntax.php
new file mode 100644
index 0000000..3025156
--- /dev/null
+++ b/syntax.php
@@ -0,0 +1,34 @@
+<?php
+class syntax_plugin_usetheme extends DokuWiki_Syntax_Plugin
+{
+    public function getType()
+    {
+        return 'substition';
+    }
+ 
+    public function getPType()
+    {
+        return 'block';
+    }
+
+    public function getSort()
+    {
+        return 156;
+    }
+
+    public function connectTo($mode)
+    {
+        $this->Lexer->addSpecialPattern('~~USETHEME:\w+~~', $mode, 'plugin_usetheme');
+    }
+
+    public function handle($match, $state, $pos, Doku_Handler $handler)
+    {
+        $match = substr($match, 11, -2); // cut match down to the template name
+        return array(strtolower($match));
+    }
+
+    public function render($format, Doku_Renderer $renderer, $data)
+    {
+        return ""; // show nothing, we want to change the template
+    }
+}
\ No newline at end of file