Heat soup in a small saucepan or in a microwave oven.
In a medium bowl, stir gelatin into cold water. Mix hot tomato soup into the gelatin liquid.
In a medium size mixing bowl, combine cream cheese and mayonnaise together. Mix soup mixture into the mayonnaise and cream cheese mixture. Mix well. Add shrimp, celery, and green onions.
Spoon the mixture into a 1 quart mold and refrigerate for at least 1 hour, but preferably overnight. Unmold onto a serving plate before serving.
