I am using a two-sided book class, with titlesec package and a redefinition of my part title style.

I want my parts' titles to be one the right page and to write a small intro text on the left page just behind. This text is no chapter nor anything referenced in the toc.

I tried :

```
\documentclass[twoside,12pt,openright]{book}
\usepackage{titlesec}
\titleformat{\part}[frame]
  {\bfseries\Huge}
  {\filright\large\enspace{\partname}\enspace}
  {40pt}
  {\Large\filcenter\MakeUppercase}
\begin{document}   
\makeatletter
\@openrightfalse
\part{part I}
bla bla bla
\@openrighttrue
\makeatother
\end{document}

```

but my part title goes on the left side.

If I do :

```
\documentclass[twoside,12pt,openright]{book}
\usepackage{titlesec}
\titleformat{\part}[frame]
  {\bfseries\Huge}
  {\filright\large\enspace{\partname}\enspace}
  {40pt}
  {\Large\filcenter\MakeUppercase}
\begin{document}
\part{part I}
\makeatletter
\@openrightfalse
bla bla bla
\@openrighttrue
\makeatother
\end{document}

```

there is a blank page after the part title one.

Any idea ?