4. Killer In The Midst
A very compelling yet disturbing twist found within "Sunshine" happened during the conclusion of the film's second act, where the survivors of the Icarus II abandon the Icarus I, only to bring back with them the sole survivor of the expedition, Captain Pinbacker. There are three elements that give this twist quality and substance. The first and most disturbing is that of Pinbacker's initial goal at killing both crews. When Capa and his crew board the Icarus I they discover the ashes of the remaining crew by exposure to the sun's harmful rays. Mace, while on his trek to find supplies in the hope it will help the mission, finds a video pertaining to the events during the voyage of the Icarus I, with Captain Pinbacker giving a monologue on how he purposely sabotaged the Icarus I's mission to save humanity. His purpose was because of his high faith in his religion, as he believed it was the "will of God" to have the sun burn out and us die. That, in the end, we were all expendable to God's work and that he, himself, would be the harbinger of God's will. Cut to the end of the second act and we discover that Pinbacker was alive the whole time inside the Icarus I, burned from head to toe because of the sun yet still alive and kicking, and managed to sabotage the Icarus II airlock, resulting into both Harvey's death and Searle's choice to stay behind. Now it was Pinbacker's turn once again to subvert the Icarus II's mission and finish what he started, all in the name of God and true justice. So he intended on killing all the crew mates and disabling their ability to deliver the payload to its destination. At first this twist seemed a bit too far out for me because it bordered on a cop-out plot device that I didn't think would do the film any justice. That was until I started thinking about the longevity of the situation; of how it has strong ties with the human condition and a strong dose of religious turmoil. Which leads to the second element: the human condition of Pinbacker (relating to #5 on this list). Let us take some time to understand his plight for a second: he, like everyone else, was trapped inside a tightly contained ship for God knows how long, surrounded by other crew mates who had desires and goals of their own. He also had command over the crew and was partially responsible for the delivery of the ship's payload into the sun. As stated with the team of Icarus II, all that weight and pressure was squarely diverted and externalized on his shoulders and everyone else. Now he has that feeling of "what if this doesn't work and we were meant to die all along?" After spending so many years in space with no physical contact from your own family and friends, where you're forced to live a sheltered life inside a hulk of metal, teamed up with others who are thinking the exact same thing, somewhere down the line something is bound to snap from within. And all that pressure is what caused a disconnect within Pinbacker, sparking the initial devastation of the Icarus I mission.
The third and final element of religious turmoil drives this twist into something that falls in line with the human condition, but at the same time is something else entirely. Pinbacker, a devoted man of a religion unknown in the film, purely based the failure of the mission on the equation of it being God's will. All the seeds of hopelessness planted firmly within the ship were finalized by Pinbacker's ultimate choice to forcefully end the mission per his allegiance with God over his own kind. And after the Icarus II seemed to dock with Pinbacker's ship, he quietly made his way aboard and began anew what God Himself believes was right. That by disabling the Icarus II and rendering the ship incapable of carrying out the payload delivery, he would see mission as Harbinger of Humanity's End done. Let's face facts here: Pinbacker was a nut, and a sick one at that. Adding a slasher element to "Sunshine" seemed to be a smart idea because it ties in well with how the human condition can be broke down and how a man puts his faith and the salvation of God's will before the salvation of those he was sent to save and protect.