Removing in example sentence
Several previous commenters have identified the contributing factors that make it so successful and memorable not least being the prevailing fashion in 30s and 40s Hollywood for lavishing attention and detail on ensemble playing rather than just two leads as so often happens today - try, for example, removing Ugarte, Ferrari, Renault etc from Casablanca and yes you'd still have Rick and Ilsa and Viktor Lazslo but they'd just be frosting without the rich cake mixture below.