Whisk together 1/2 cup olive oil, 4 tbsp lemon juice, minced garlic, chopped parsley, smoked paprika, oregano, red pepper flakes, kosher salt and black pepper in a medium bowl until combined.

Divide marinade

Reserve about 3 tbsp of the marinade in a small bowl to use as a finishing drizzle. Pour approximately 1/3 of the remaining marinade into a bowl for the shrimp, 1/3 into a shallow dish for the calamari, and 1/3 into a bowl for the scallops. This ensures even but brief marinating times for each seafood.

Grilled Shrimp

Marinate shrimp

Place shrimp in the bowl with the portioned marinade. Add lemon zest. Toss to coat, cover, and refrigerate for 15–20 minutes (no more than 30 minutes to avoid 'cooking' the shrimp in acid).

Prepare skewers and grill

If using wooden skewers, soak them in water for 20 minutes while shrimp marinate. Preheat grill to medium-high (about 400–450°F / 200–230°C). Thread 4–6 shrimp per skewer, leaving a little space between each. Oil the grill grates lightly. Grill shrimp 2–3 minutes per side until opaque and pink with light char marks. Remove from grill to a platter and tent loosely with foil.

Grilled Calamari

Prep calamari

Slice tubes into 1/2-inch wide rings if desired, or leave whole for grilling crosswise. Pat dry thoroughly with paper towels to ensure good sear. Toss the calamari in the portioned marinade in the shallow dish for 10 minutes only (longer will make it tough).

Grill calamari

Brush grill grates with oil. Grill calamari over high heat (about 450–500°F / 230–260°C) for 1–2 minutes per side for rings or whole tubes; tentacles may take 2–3 minutes. You want quick, high heat to develop char without overcooking. Brush lightly with the reserved 2 tbsp olive oil if they begin to stick. Sprinkle coarse sea salt immediately after removing from grill.

Grilled Scallops

Marinate scallops briefly

Pat scallops very dry. Place scallops in the bowl with their portion of marinade and toss to coat. Let stand at room temperature for 10–15 minutes only.

Sear on the grill

Preheat grill area to very high heat (grill or a heavy cast-iron skillet set on the grill). Oil the grates or skillet lightly. Place scallops on the hot surface 1 inch apart. Sear 1.5–2 minutes without moving until a golden crust forms, then flip and cook another 1–2 minutes until just opaque in the center. Avoid overcooking (scallops should be tender). Transfer to a platter and immediately brush with melted butter and sprinkle chopped chives.

To serve

Arrange grilled shrimp, calamari and scallops on a large platter. Drizzle the reserved 3 tbsp marinade over the seafood, then squeeze lemon wedges over top. Scatter additional chopped parsley and serve extra lemon wedges on the side.

Serve immediately while hot with crusty bread or a simple salad and enjoy.