How was this possible?

In the mid-season finale, we finally get some answers to who Harrison Wells actually is and we finally see Flash and Reverse-Flash interact. However there's a scene in which S.T.A.R. Labs and the police team up to capture Reverse-Flash. In the scene, Wells is seen interacting with him while he's trapped within their barrier. We also see Reverse-Flash run up to Eddie and instead of killing him turn his attention to Joe, which is something Eddie actually addresses later in the episode. At the end of the episode, we actually learn that Harrison Wells and Reverse-Flash are one in the same. So, how was Wells able to have a full fledged conversation with himself in two different locations and how was he able to actually 'fight' himself inside the barrier?