Url for trailer.  This a short tutorial for you in case you don't know how to add video on your fanfic.  
Step one. Find a video that you want to add into your fanfic
Step two. Find where the embeb link is which I'll give you down below
Step three. Copy the link and go to your fanfic. Click source and paste the link 
Step four. Click source again and wala! You get your video. It will  show a box with "iframe" word in it 
Step five. Click on the iframe and right click. It will show iframe properties. Click it and resize your iframe
Step six. Once done, save your work and click view. 

          Here's the link for your video : 
 < iframe frameborder="0" height="255" scrolling="no" src="//www.youtube.com/embed/WPGWo-d1akA" width="555">  
           Don't forget to delete the space  btw iframe and >  i

If you do follow the tutorial that I did up there or you do know how to put the video to your fanfic it will turn out like this : 

     
                                                               I have resize it so it be like this ^