But a love of the theater can help you appreciate Mike Leigh's meticulously detailed valentine to performers of the 19th century. But it's not really. This slice just happens to be set 100 years ago, and it's populated with historical characters instead of fictional. Each man claims that he subverts his own gifts to the work of the other. This isn't a biopic per se.
Most biographical movies look at their subjects from the outside in.
It places us in the midst of the lives, triumphs and frustrations of Gilbert, Sullivan, their actors and their loved ones. The actors include longtime Leigh collaborator Timothy Spall as an insecure baritone and Kevin McKidd as the opera company's romantic lead, a Scotsman who objects to the leg-revealing kimono he's required to wear. Leigh revels in the process of work and creation. That includes a beautifully sustained rehearsal scene between Gilbert and his actors, as the writer-director tells his cast exactly how to speak a line and move. We also witness Sullivan guiding his orchestra, politely pointing out the mistakes they've made in their playing.