Complex sentence: Film noir, to which lower budgets lent themselves, became something of a house style at the studio; indeed, the RKO B "Stranger on the Third Floor" (1940) is widely seen as initiating noir's classic period.
Split into simpler sentences: Film noir, to which lower budgets lent themselves, became something of a house style at the studio. Indeed, RKO B "Stranger on the Third Floor" (1940) is widely seen as initiating noir's classic period.