As part of their secret investigation of The RAC, the Killjoys accept a ghost warrant to rescue three missing Killjoys lost in the heart of the Badlands. The mission leads them deep underground into an abandoned mine, where the bounty hunters become the hunted.
Killjoys follows a trio of hard-living bounty hunters - Dutch, John, and D'avin - taking on interplanetary missions, chasing and capturing deadly criminals throughout a distant system named the Quad. They have sworn amongst themselves to remain neutral during a bloody, multi-planetary class war that threatens to destroy the Quad. However, their own pasts and the events around them begin to draw them in deeper to this dangerous vortex of war.