Highway Killers tells the story of two friends who rent a car and start killing people who cross their path. The two men, who set out on the road after renting a car, begin robbing shops and gas stations along the highway under the influence of heavy drugs. Meanwhile, the pair, who start killing people who cross their path with a pump-action shotgun, make plans to flee the country via the southern border.

Sinan (Mert Firat) and Olcay (Acelya Devrim Yilhan) are two young people who have broken up with their lovers and lost their faith in love. After they have found each other, they start all over again. However, things get complicated when Sinan's ex-fiance shows up and Olcay starts to act strange.