Bring a large pot of lightly salted water to a boil. Add pasta and cook for 3 minutes or until al dente; drain.
Melt butter in a large frypan over medium heat. Saute garlic until tender. Stir in cream and cook until thickened, about 5 minutes. Add crab, prawns, Parmesan cheese and salt and pepper. Reduce heat to low and cook for 2 to 3 minutes, until heated through.
Transfer cooked linguine to a serving platter and top with seafood sauce. Garnish with parsley.