At first blush, the relationship between Masters and Johnson feels analogous to the one between Don Draper and Peggy Olson. Johnson is put in the position of having to prove herself to an older man who, in some ways, is right in step with the pre-Second-wave feminism ideology of the '50s. Only Johnson is far more confident than Olson, and Masters isn't the anti-hero that Draper is.
Masters is no angel, but he doesn't have a Big Secret like Don. (The secret he has is more like a medium-size secret, and doesn't involve a double life or any dead people. In the same way that Mad Men has only become better, richer, and more unpredictable the further away it gets from the Big Question of who will learn Don's secret, Masters of Sex begins in a place where the issue of "When will he be exposed?" isn't the driving engine of the narrative.)
Masters's personality issues have to do with his scientist's perspective on the world. He's a Vulcan. Everything is a procedure. Cold rationality trumps passion, including any hot-blooded ideas about what's underneath the drawers of others. Except we know he'll crack. There will be #feelings on this show just as surely as there will be more camera dildos. —Ross Scarano