Dr Wells dead body in Starling City
Dr Wells' dead body in Starling Cityscreenshot/youtube

As Season 1 of "The Flash" moves steadily closer towards the finale, one question remains to be answered: "Who is Harrison Wells?"

Audience know that he is Eobard Thawne, a scientist from the future who killed Dr Wells and took his body; but, how long will it take for Barry and others to find out? While Barry is working through his emotions regarding what he knows about Dr Wells, there is a new Meta-Human menacing the streets of Central City, a shape-shifter.

"All Star Team Up" ended with Barry (Grant Gustin) telling Caitlin (Danielle Panabaker) and Cisco (Carlos Valdes) that he believes Dr Wells (Tom Cavanagh) is the Reverse Flash and that he killed his mother. Although Caitlin is not convinced, Cisco reveals that he has been having very realistic dreams about his mentor confessing that he is the Reverse Flash before killing him.

These, however, aren't dreams; they are snippets from events that happened in real time before Barry accidentally messes up the time structure in "Rogue Time".

Following their discussion, Cisco and Joe (Jesse L Martin) head over to Arrow's Starling City to find out what happened the day Dr Wells and his wife Tess Morgan met with an accident. According to Wells' nemesis Dr Tina McGee had told Barry in "All Star Team Up" that he has been acting like a completely different person since then. In "The Flash" - "Arrow"crossover episode, Joe and Cisco realise that the person that looks like Dr Wells is in fact someone completely different, after they see the dead body of the real Harrison Wells in a morgue.

Although he is plagued by what else Dr Wells may be hiding, Barry still has to stop meta-humans from looting Central City. In this episode, it is a shape-shifter, who will be played by about 20 different actors. Barry explains to Caitlin and Dr Wells, "I literally saw a grown man morph into a teenage girl."

Caitlin warns Barry that if the shape-shifter touches him while he is dressed as "The Flash", the meta-human could expose his identity to the rest of Central City or Iris (Candice Patton), who seems to be the only person left in the dark, especially after Eddie (Rick Cosnett) was also let in on the secret. Another aspect to keep in mind during the episode is that Eobard Thawn not only has Flash-like abilities, but also shape-shifting abilities as was proved when he shifted his form to look like Dr Wells.

Watch out for Season 1 episode 19 of "The Flash", titled "Who Is Harrison Wells?", on 21 April, Tuesday at 8.00 pm (EST) on The CW.