2. Owen Slater
Owen (Charlie Cox) was never meant to be a permanent fixture on Boardwalk Empire. Since his introduction in season two, he became one of the shows most likeable and charismatic figures. It was too good to be true. His roguish charm mixed with quiet menace and being a capable workhorse for Nucky made him the perfect addition. But, be it his secret love affair with Margaret (Kelly MacDonald) or the danger of working for the under-fire Nucky, Owen was always going to be fighting the odds. His fate was sealed upon hearing Margaret was pregnant with their child. Not that his ultimate demise was shocking, but the way in which it was handled and shown to the viewer is and is one of the best reveals the show has done. Rather than having his death shown on-screen, Owens death is kept off-screen and is the truly shocking part. We witness news of his death from Margaret and Nuckys point of view, who find his body stuffed into a crate. The reveal not only shows the loss of one of the shows most promising characters, but also all but confirms to Nucky of his and Margarets relationship, an extra kick in the teeth for Nucky.