Cook the Pasta: Bring a large pot of salted water to a vigorous boil. Add linguine and cook according to package instructions until al dente, about 8-10 minutes. Reserve ½ cup of cooking water, then drain the pasta and set aside.

Sauté Aromatics: In a large skillet, heat olive oil over medium heat. Add minced garlic and red pepper flakes, sauté for 1-2 minutes until garlic is fragrant but not burnt.

Deglaze and Add Shellfish: Pour in white wine to deglaze the pan. Add soaked clams and mussels. Cover and cook for 3-5 minutes until shells open.

Incorporate Shrimp: Remove lid, add shrimp to the skillet. Stir gently, re-cover, cook for an additional 2-3 minutes until shrimp are pink and opaque.

Add Calamari and Scallops: Include calamari and scallops into the skillet. Cover and cook for another 2 minutes.

Combine with Sauce: Stir in tomato sauce along with reserved pasta water. Simmer for 2-3 minutes. Discard any unopened shells.

Toss with Linguine: Add drained linguine to the skillet, tossing gently to combine with the sauce. Cook for 1-2 minutes on low heat until heated through.

Plate and Garnish: Serve immediately, garnish with chopped parsley.