Watch on SFlix. Stiffelio is considered "early Verdi" to musiclogists who classify things, but, in reality, it is a final transition between the maestro's earlier (but most enjoyable) works, and the mature craftsmanship of Rigoletto. Preceded by Luisa Miller (q.v.), there is more dramatic intensity and story line than in the earlier works. The plot centers around Stiffelio, a minister, who discovers that his wife, Mina, has been unfaithful.