Jewel of The Stars. Season 1 Episode 3 The Legacy of War

Tourists on a cruise. Stranded in an alien battleground
When their warp drive mysteriously stops working, the luxury cruise ship Jewel of The Stars becomes easy pickings for humanity's enemy - the Dracnor. And there may be an enemy agent on board.
Before the fall of Earth, a madman made doomsday predictions on Captain Les Miller's doorstop. How did he know the invasion was coming? Now that same man has been spotted walking the promenade. Les must stop him, but the evidence contradicts what he knows to be true.
Will the legacy of an ancient war mean the end of the galaxy's last free humans?