NoMethodError in Articles#show

Showing /home/app/drghaly/app/views/articles/video.html.haml where line #1 raised:

undefined method `html_safe' for nil:NilClass
Did you mean?  html_safe?
Extracted source (around line #1):
1
              
= embed_video(@multimedia.first).html_safe

Rails.root: /home/app/drghaly

Application Trace | Framework Trace | Full Trace

Request

Parameters:

{"content_type"=>"video",
 "article_id"=>"13140"}

Response

Headers:

None