Marlene Dietrich became an immediate international star on the strength of her performance as the temptress Lola Frohlich in Josef von Sternberg's classic tale of love and obsession. Professor Immanuel Rath (Emil Jannings) is a strict and humorless schoolmaster who is shocked when he discovers the boys in his class have been spending their time at a sleazy cabaret called The Blue Angel, where an entertainer named Lola (Dietrich) keeps the men in thrall and sells suggestive postcards of herself. Rath goes to the club in hopes of catching his students and giving them a severe dressing-down, but he instead finds himself entranced by the carefree atmosphere of the club, and is struck by Lola's earthy, sensual beauty. Rath finds himself strongly attracted to Lola, and she later entertains him in her dressing room. When word of Rath's infatuation with Lola spreads to his students, he is taunted mercilessly, and eventually Rath is dismissed from the school. While Lola agrees to marry Rath, she shows little affection for him and delights in humiliating him, making him her servant and forcing him to play a clown in her stage show. The Blue Angel was shot in both German and English language versions; the German is preferable, as most of the cast were obviously more expert in that tongue. Dietrich introduced her theme song, "Falling In Love Again", in this picture.
~ Mark Deming, All Movie Guide