The painter, Marcello, and the writer, Rodolfo, share a Parisian garret studio. It is Christmas Eve and both young men are poor and cold. Soon they are joined by two more Bohemian acquaintances - the philosopher, Colline, and the musician, Schaunard. The latter has recently earned a little money and so the friends decide to go off and celebrate in the Latin Quarter, first, skillfully avoiding paying rent to the landlord, Benoit. Rodolfo says he has to stay behind, briefly, to complete an article. Soon he is interrupted by Mimi, a young seamstress, asking for a light for her candle. Mimi is ill yet Rodolfo is immediately charmed by her. His friends call out for him to hurry. He and Mimi declare their love and set out for the CafÃ© Momus.
With the four friends and Mimi reunited in a bustling thoroughfare imbued by festive atmosphere, the spell is broken when Marcello sees his old flame, Musetta, walk by on the arm of a rich, old diplomat, Alcindoro. She soon dispatches Alcindoro to buy her a new pair of shoes and flirts again openly with Marcello. After much merriment, the bill for supper arrives and a returning Alcindoro finds he has to settle it as the Bohemians make their escape amongst the hubbub of an arriving military band.
Two months have passed and it is February. Mimi, afflicted by TB, is looking for Marcello to tell him how Rodolfo is tormenting her by his constant possessiveness. She retreats when Rodolfo appears to confide in Marcello his grave concerns over Mimi's illness. He and Mimi agree they must part, whilst Marcello and Musetta also seem to be in the throes of separation.
In early spring, Marcello and Rodolfo are alone again, feigning indifference to their respective lost loves. Schaunard and Colline appear with some meagre provisions and the quartet again try to look on the bright side. The mood is shattered by Musetta who has come to announce that Mimi is outside dying. She is brought in and the Bohemians scrape some money together for a doctor. Left alone, Mimi and Rodolfo fondly remember their first meeting and Mimi gently drifts off - until Schaunard realizes her new-found rest will be permanent.