Last week in "The Flash" viewers watched in awe as Caitlin finally believed the crippled man claiming to be Harrison Wells is actually the Reverse Flash. Barry Allen revealed that the real Harrison Wells has been dead for the last fifteen years, which was enough proof that he is the Reverse Flash.

Episode 20 suitably named "The Trap" will finally see the people who know about the doctor's true identity doing something about it. As per the Flickering Myth, Barry, Caitlin, Cisco and Joe set a trap for Wells. However, the plan requires that Cisco uses himself as prey which puts him in grave danger. In other news, Eddie makes a decision regarding Iris that leaves Joe a bit unsettled.

Executive producer Andrew Kreisberg also provided more information about the plan to TVLine. He said that Cisco's flashes of the alternate timeline will provide the key to the plan. Iris will finally learn of Barry's secret identity and she won't be happy about it because all the men in her life lie to her. "The Flash" fans will also be extensively treated since the show's penultimate episode will see quiet a gathering of super-villains. Captain Cold, Lisa Snart, The Mist, Deathbolt, Peekaboo, The Rainbow Raider and The Weather Wizard all return and will have a strange alliance. They return courtesy of Wells' actions which threaten the integrity of the pipeline prison.

Kreisberg went on to tease about the finale episode, claiming that it will provide clarity about the night Barry's mother died. The emotional finale will also give fans an explanation as to why Cisco is able to access a timeline that no longer exists.

Can the team stop Harrison Wells? Will he reveal his true self? "The Trap" airs on Tuesday, April 28 at 8 p.m. ET on CW.