David Morrissey as Stephen Collins
His character's intriguingly complex: driven, ambitious, self-involved, impulsive, childish; both principled and immoral, and, amazingly, mostly sympathetic. I liked and felt for Stephen most of the time. But by the end, I'd had enough of him. Some of that may have been the writing: it's extremely difficult for an actor to sustain the audience's sympathy when it's greeted by an endless series of his character's half-truths and poor judgment. But part of my final antipathy for Stephen was due to Morrissey--he doesn't do anguish well, and unfortunately Stephen is anguished half the time.
There was much I liked about Stephen that Morrissey brought to him: his virility, his straightforwardness, his integrity (in certain areas). He comes across as a guy's guy, intrinsically likable. The hearing scene when he so effectively rebutted that obnoxious American oil industry shill was terrific--it made me see why Stephen was considered a rising star in the party. But it would probably take Streep or Penn to keep you interested in a character who's racked with pain & guilt for hours on end.