17. Sherlock - Season 2 Finale (The Reinbach Fall)
Everyone knew he would find a way to cheat his 'death', but the second season of Sherlock still left fans stunned and scratching their heads as Sherlock jumped off the building following his final confrontation with Moriaty. Viewers saw Sherlock hit the ground and Watson discover his bleeding, broken body. Our eyes told us one thing while our hearts told us another. The clever thing about the dramatic finale was trying to puzzle out how he survived that fall. It was something the season three opener The Empty Hearse played on brilliantly with three alternate solutions. Was it a dummy? Did he jump onto a giant inflatable cushion? Was he suspended by wires? Few cliffhangers have raised so many questions. It certainly left audiences desperate for more and that is exactly what a good season cliffhanger is all about.