The flash finale
Details of The Flash season 1 finale have surfaced online TheFlash/Facebook

The Flash is just four episodes away from its epic season finale, which will feature a major showdown between Harrison Wells and Barry Allen.

Grant Gustin, who plays The Flash, took to Twitter to announce that he has wrapped filming for season 1.

The actor also shared a picture of himself from the last day of filming on Instagram.

I just got wrapped on season 1 of The Flash & the sun is up. ????⚡️

A photo posted by Grant Gustin (@grantgust) on

The synopses of the final few episodes of The Flash are out.

Episode 19 is titled Who Is Harrison Wells, and will air on 21 April, on The CW.

Joe (Jesse L. Martin) and Cisco (Carlos Valdes) head to Starling City to continue their investigation of Dr. Wells (Tom Cavanagh). While in town, the duo enlists the help of Captain Lance (guest star Paul Blackthorne), and Cisco meets the Black Canary (guest star Katie Cassidy), who asks him for a favor. Meanwhile, back in Central City, Barry (Grant Gustin) races to catch a meta-human named Hannibal Bates (guest star Martin Novotny) who can transform himself into every person he touches - which includes Eddie (Rick Cosnett), Iris (Candice Patton), Caitlin (Danielle Panabaker) and even The Flash.

Episode 20 is titled The Trap, and will air on 28 April, on the CW.

Barry (Grant Gustin), Caitlin (Danielle Panabaker), Cisco (Carlos Valdes) and Joe (Jesse L. Martin) set a trap for Wells (Tom Cavanagh). Cisco uses himself as prey which puts him in grave danger. Meanwhile, Eddie (Rick Cosnett) makes a decision regarding Iris (Candice Patton), which leaves Joe a bit unsettled.

Episode 21 is titled Grodd Lives, and will air on 5 May at 8pm on The CW.

Barry (Grant Gustin) must deal with the Reverse Flash's (Tom Cavanagh) latest threat to a member of the group. To make matter worse, Dr. Wells unleashes Grodd on the city in order to distract Barry and the team. Joe (Jesse L. Martin), Barry and Cisco (Carlos Valdes) head down into the sewers to catch Grodd but the gorilla quickly gets the upper hand after he kidnaps Joe. Iris (Candice Patton) and Barry have a heart to heart talk.

Episode 22 titled Rogue Air and Episode 23 titled Fast Enough, will air on 12 May and 19 May respectively.

Fast Enough will serve as the series finale for The Flash's pilot season, where superheroes will unite to fight the Reverse Flash.

The flash finale
The Flash teams up with Arrow and Firestorm in a new promo video YoutubeScreenshot

According to spoilers, the finale will feature a showdown between Barry Allen and Harrison Wells/Eobard Thawne.

The pilot season's arc has been built around whether or not Barry will get justice for his mother, and save her from the man in the yellow suit. One way or the other, we just hope that there are a few loose ends still open for the next season.

Meanwhile, a new promo shows Gorilla Grodd wrecking havoc in Central City in episode 21.

How will the show end? Let us know your opinion in the comments section below.