Melt 2 tablespoons butter over medium heat. Cook shrimp 2-3 minutes until pink. Remove and set aside.
Add remaining butter and cook onion, garlic, celery, and carrot 4-5 minutes until soft.
Sprinkle flour over vegetables. Cook 1-2 minutes to make roux.
Slowly whisk in seafood broth until smooth.
Add cream, wine, Old Bay, cayenne, salt, and pepper. Simmer 10-15 minutes until thickened.
Fold in crab, lobster, and shrimp. Simmer 5 minutes more.
Garnish with parsley and serve with lemon wedges.
