This film is a fascinating showcase for Emil Janning's theatrical play. He's a gentle school teacher who believes in his boys and is easily fooled about all things, while the other town officials want him dismissed. Curiously it's very hard to see what the film is exactly aiming for. Disaster strikes and the lax prof proves to be too far removed of the real problems of the world, on the other hand his enemies are shown in the most unsympathetic, satirical way denouncing the militaristic, bourgeois ideology of the Kaiserreich.

Prim professor Immanuel Rath finds some of his students ogling racy photos of cabaret performer Lola Lola and visits a local club, The Blue Angel, in an attempt to catch them there. Seeing Lola perform, the teacher is filled with lust, eventually resigning his position at the school to marry the young woman. However, his marriage to a coquette -- whose job is to entice men -- proves to be more difficult than Rath imagined.

Based on the real life events of the 1927 Steglitzer Schülertragödie, in which several high school students planned murder-suicides.