diff --git a/autoload/dpp.vim b/autoload/dpp.vim
index 96e5b80..5c3c466 100644
--- a/autoload/dpp.vim
+++ b/autoload/dpp.vim
@@ -1,6 +1,9 @@
 function dpp#get(name = '') abort
-  return a:name ==# '' ?
-        \ g:dpp#_plugins->copy() : g:dpp#_plugins->get(a:name, {})
+  return !'g:dpp#_plugins'->exists()
+        \ ? {}
+        \ : a:name ==# ''
+        \ ? g:dpp#_plugins->copy()
+        \ : g:dpp#_plugins->get(a:name, {})
 endfunction
 
 function dpp#source(
@@ -15,6 +18,11 @@ function dpp#sync_ext_action(ext_name, action_name, action_params={}) abort
     return
   endif
 
+  if !'g:loaded_denops'->exists() && !dpp#get('denops.vim')->empty()
+    " Load denops.vim
+    call dpp#source('denops.vim')
+  endif
+
   if !'g:loaded_denops'->exists()
     call dpp#util#_error(
           \ 'denops.vim must be loaded before "dpp#sync_ext_action()".')
@@ -32,6 +40,11 @@ function dpp#async_ext_action(ext_name, action_name, action_params={}) abort
     return
   endif
 
+  if !'g:loaded_denops'->exists() && !dpp#get('denops.vim')->empty()
+    " Load denops.vim
+    call dpp#source('denops.vim')
+  endif
+
   return dpp#denops#_notify('extAction', [
         \ a:ext_name, a:action_name, a:action_params])
 endfunction
@@ -56,6 +69,11 @@ function dpp#make_state(
     return 1
   endif
 
+  if !'g:loaded_denops'->exists() && !dpp#get('denops.vim')->empty()
+    " Load denops.vim
+    call dpp#source('denops.vim')
+  endif
+
   return dpp#denops#_notify('makeState', [base_path, config_path, a:name])
 endfunction