The Supreme System Lord Ra has been missing for a year. As a consequence, the System Lords are straining their bonds, at a perilous time. The alien Covenant has proclaimed the Goa'uld and their servants, Jaffa and Human alike, as False Gods and Heretics to be exterminated. Meanwhile, in a distant corner of the galaxy, the beleagued UNSC struggles for survival against a splinter of the Covenant's might, while the 12 Colonies of Kobol are none the wiser of the dangers in the dark.