Prepare a grill or grill pan for high heat. Soak four 12-inch skewers in water for at least 30 minutes
Put the shrimp in a large resealable plastic bag. Add 2 tablespoons of the oil, oregano, crushed red pepper, 1 clove grated garlic and the zest and juice of 1 lemon. Seal the bag tightly and use your hands to lightly massage the marinade into the shrimp. Marinate for 15 minutes at room temperature.
Meanwhile, heat 1 tablespoon of the oil in a medium saucepan over medium heat. Add the couscous and cook, stirring occasionally, until toasted, about 3 minutes. Add the remaining 2 cloves grated garlic and cook, stirring, about 1 minute. Add 2 1/4 cups water, the raisins and 1 teaspoon salt. Bring to a boil. Cover, reduce the heat to low and cook until all the water has been absorbed and the couscous is tender, about 12 minutes. Transfer the couscous to a large bowl and stir with a fork to break up any clumps and release excess steam. Set aside.
Thread about 5 shrimp on each skewer. Lightly oil the grill grates. Grill the shrimp until lightly charred in spots on both sides and just cooked through, 1 to 2 minutes per side. Add the remaining 3 tablespoons oil, the feta, olives and parsley to the couscous. Finely grate the zest of 1 lemon and add it to the couscous along with its juice and the juice from the remaining lemon and toss to combine. Season with salt and pepper and divide among 4 plates and top with the shrimp.
Copyright 2016 Television Food Network, G.P. All rights reserved.