"Business as Usual" is the 116th episode of the television series Star Trek: Deep Space Nine, the 18th episode of the fifth season. It aired in 1997.

Despondent over his mounting financial woes, Quark allows his cousin Gaila to talk him into joining the arms sales business.

Quark and Jadzia Dax are playing Tongo in the bar, but the Ferengi's heart isn't in it. His debts are mounting and he will soon have to sell his establishment. Quark's cousin Gaila enters the bar and offers to help him out of his predicament. Quark knows immediately what the enterprise is - selling weapons. Gaila tells him that no weapons will be brought to Deep Space Nine, as Odo would stop them. Instead, Quark will use his skills with customers to display holographic versions of the weapons in the holosuites. The weapons will be supplied by the suavely sinister Hagath. Gaila claims the money will help him pay off his debt, help renew his business license and enable him to buy his moon.

Quark turns out to be a natural at selling weapons and the scheme becomes quite profitable, but it quickly alienates Quark's former friends, particularly Jadzia. Quark's latest client, the Regent of Palamar, who is at war with General Nassuc, says he wants to make a purchase that will kill somewhere in the region of twenty-eight million of his opponent's people. Galia and Hagath take the matter lightly, but Quark is horrified at the idea of being responsible for so much death.

Quark realizes he must find a way to escape with his life and avoid being part of a genocide program. He invites General Nassuc to the station on the pretense of supplying weapons to both sides, inspired by Hagath's previous dealings. He arranges for representatives of the two sides - the Regent of Palamar, and General Nassuc - to encounter each other in a cargo bay, making himself conveniently absent in the process. A firefight ensues, and they leave the station in pursuit of the double-crossing Gaila and Hagath.

Quark's friendship with Jadzia is renewed, but his financial woes are not over: Sisko makes him pay for damage ensuing from the firefight.

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