Has anyone else watched Nasa'a unexplained files?

I just did.
There are so many stars in our Galaxy. Many more in the Universe. Isn’t it more likely than not that alien life exist? Have we been observed?
This question is for fun.
Here is the link to the show.

http://science.discover y.com/tv/are-we-alone/n asa-files-the-unexplain ed.html