Star Trek: Deep Space Nine – The Complete Series – To Buy

According to CheapCharts this is the lowest price the series goes to when on sale.
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A spin-off of Star Trek: The Next Generation, Deep Space Nine is set on a space station orbiting the planet Bajor. This time, Commander Benjamin Sisko is in charge of a diverse crew. But unlike other Star Trek series, theres no USS Enterprise to help them. Sisko and the crew must fight off rival alien species who want control of Deep Space Nine because of its strategic position close to a wormhole, which allows speedy travel to the far reaches of space.