If I go with the most recent revision of the crawl I posted, I will need to change the second sentence from, “plotting their return to power,” to, “plotting its return to power.”
‘The First Order’ is a singular subject, and another verb in the sentence already treats it as such (“has risen”).

So, the first paragraph would read: Luke Skywalker has vanished. In his absence, the sinister FIRST ORDER has risen in secret from the ashes of the fallen Empire, plotting its return to power."