In a bowl, beat cream cheese until softened. Add horseradish, mustard, and dill seed; beat until smooth.
Arrange roast beef slices on a work surface. Gently spread cream cheese mixture over the top of each beef slice. Roll each prepared roast beef slice into a long roll (roll up tightly as possible).
Wrap each roll with plastic wrap and refrigerate for approximately 1 to 2 hours before serving.
To serve, cut rolls into 1-inch slices and arrange, cut side up, on platter.
Serves 6 to 8.
Roast Beef Roll-Ups Recipe: https://whatscookingamerica.net/appetizers/roastbeefrollups.htm