Ella was excellent, Franchot was unavoidably over-the-top (But he played similar parts in other films such as "The Man on the Eiffel Tower") and Alan was nearly non-existent but the film certainly "thrilled".
*mild spoiler ahead*: I wonder how many times Elisha Cook got strangled in his films but I seem to recall various other examples. I will avoid naming the murderer but I think it's necessarily obvious because of the plot "thriller" demands.
A very well-done but dated film noire (for example: everyone smoked like crazy and the police were really stock characters. And no dead bodies were ever shown, unlike today's gore fests.) done in the familiar short-scene tableaux format of the period.
8 out of 10.