Stargate Universe Season 1 Episode 19 (Stargate Universe s01e19) with title “Incursion (1)” airs on Friday, June 4th 2010 at 09:00 pm via Syfy.
Here is summary for Stargate Universe Season 1 Episode 19 :

An enemy from the Milky Way has boarded the Destiny and has taken hostages. Is it possible that they know how to get back or have they stranded themselves as well?

Few hours after original series aired on TV, online streaming video for Stargate Universe Season 1 Episode 19 usually available on Net and of course, if video available, as soon as possible will show you where you can watch this episode for free.