Seafood Mousse

1 can cream of mushroom soup
1 cup mayonnaise
6 ounces cream cheese
1/2 teaspoon Worcestershire sauce
1/2 teaspoon seasoned salt
1 tablespoon grated onion
1 1/4 pounds cooked, cleaned shrimp, finely chopped
1 (6 1/2 ounce) can crabmeat
3 envelopes unflavored gelatine
1 cup cold water
Red food coloring

Cook first 6 ingredients in top of double boiler over medium heat. Stir until smooth. Add shrimp and crabmeat. Dissolve gelatine in cold water; blend into mixture. Add 2 to 3 drops red food coloring. Pour into 6-cup mold and chill until firm.