I don't know where the title '8 Assassins' comes from, as I failed to find out who they are, where they come from, and what they are doing. I suppose the makers are referring to 'Seven Samurai', although I doubt that their target audience will ever have heard of Akira Kurosawa.
But the story sounds vaguely familiar.
Bank robber Amir runs off with the money, leaving his friends behind. It leads to a car chase through the small streets of a Moroccan town, getting bonus points for hitting fruit carts along the way. Amir drives into the desert until he finds a walled village. The village is ruthlessly governed by a local thug, Sharkan, who imprisons Amir.
In the prison, Amir encounters Shahin, who used to be the leader of a desert tribe. He is the only one who knows where a thousand-year-old treasure can be found, but he refuses to tell Sharkan where that is. To add insult to injury, Sharkan has also chosen Tarek's daughter, Aida, to be his bride.
Needless to say, Amir, with the help of Aida, manages to escape. They reach the tribe and return to the village to free Shahin, who is mortally wounded. He reveals the secret to Amir and appoints him as the new leader of the tribe.
Sharkan and Amir enter the Ali Baba cave, where they duel for the treasure. Amir, obviously, wins, although he is seriously wounded. Luckily, Aida followed them and manages to get Amir back to the village.
The movie tries to mimic Tarantino's style with choreographed, but often confusing fighting scenes that seem to go on forever. The story is thin. Basically, Amir (and friends) attack Sharkan (and gang), then retreat. Then Sharkan retaliates with his soldiers. Then it's Amir's turn again to attack Sharkan. Et cetera. This cat-and-mouse game is repeated until 99 minutes have passed and nobody seems to be interested in the plot any more.
The body count must be well over one hundred, so the local undertaker must be a very rich man. At least one who will be happy.