From the screenplay and novelization by Dean Devlin & Roland Emmerich.

Starring Beau Bridges, Michael Beach, Ben Browder.

Our heroes (including Ben Browder as fearless leader Lt. Col. Cameron Mitchell, Amanda Tapping as the intrepid Lt. Col. Samantha Carter, Christopher Judge as the implacable alien Tealć, Michael Shanks as the ever-resourceful Dr. Daniel Jackson, and Claudia Black as the irreverent Vala) have long known that the Ori are perhaps the most irresistible force theyv́e ever encountered, in part because they are "ascended" beings who dont́ exist in recognizable physical form (their spaceships do, and they're huge). But now the team faces an even greater threat: the Ori have set their sights on good ol ́Planet Earth. Thatś where the Ark comes in; if the good guys can just get their hands on it, they hope this ancient artifact will effectively put the big, bad Ori, their minions, and their entire religion (known as "Origin") out of business.