[b]STAR TREK: DOMINION[/i]
Garak's bomb in DS9's 'In the Pale Moonlight' fails to go off. The Romulans never join the war. The Dominion infects Andoria with the quickening virus. The Federation surrenders.
The players: ex-Starfleet officers and other assorted anti-Dominion types. They must build a coalition to drive the Dominion out.
First they must get a ship and a base. Then they contact the Klingons, the Taurhai, the Romulans etc to build and alliance. All the while staying ahead of the enemy.