Michelle Williams was baffled to learn of Marilyn Monroe's notorious tardiness when filming My Week With Marilyn - until she realised how long it took the blonde bombshell to get ready.
The actress insists on being punctual for her professional commitments and questioned how the tragic Hollywood icon could be so "disrespectful" to her colleagues by repeatedly showing up late on set.
But Williams admits it took just a few days to understand why the Some Like It Hot star was always behind schedule after channelling Monroe for director Simon Curtis' new biopic.
She tells CNN newsman Piers Morgan, "I was curious about that because I didn't really identify with it. How can a person be so, in a way, disrespectful of the other actors and crew people that you're working with? And after about three days into week one I realised exactly how. When you spend three-and-a-half hours sitting in hair and make-up and then are required to transmit a kind of energy and vibration that makes people feel like you're sort of existing to give them pleasure... to put all that out on a consistent basis is exhausting.
"By Thursday I had a pretty good sense of maybe one of the reasons that she wouldn't want to get out of bed and go to work."