At the end of Season One, Barry Allen/The Flash (Grant Gustin, Glee), Iris West (Candice Patton, The Game), Caitlin Snow (Danielle Panabaker), Cisco Ramon (Carlos Valdes) and Detectives Joe West (Jesse L. Martin, Law & Order) and Eddie Thawne (Rick Cosnett) all faced down the Reverse-Flash, Eobard Thawne (Matt Letscher), a man who had been impersonating renowned physicist, Dr. Harrison Wells (Tom Cavanagh, The Following) for the past 15 years. It was revealed that Eobard was trapped in the past after attempting to stop Barry long before he became The Flash, and was forced to change his plans. By impersonating Wells and causing the explosion that not only created the metahumans, but also The Flash, he would be able to harness the Speed Force and return to his own time.
Just as Eobard was about to see his plan come to fruition though, Eddie, Eobard's ancestor, kills himself to stop the evil descendant from winning. While that did stop Reverse-Flash, it created a massive singularity over Central City. Season Two starts about six months after that singularity was closed, and while the city shouts The Flash's name out as a hero, Barry feels it is not deserved. While most saw The Flash run into the singularity, what they didn't see was Dr. Martin Stein (Victor Garber) and Ronnie (Robbie Amell, The DUFF) becoming Firestorm, flying into the vortex and separating. The resulting explosion is what stopped the singularity, but it also cost the team Ronnie's life.
Between that event and the start of the season, Barry has pushed everyone away. Not wanting any more of his friends to get hurt, he runs-solo trying to stop every crime he can. Of course, he also has to balance his day job as a CSI, and he also takes time out at nights to repair businesses that are still damaged from the singularity.
Forcing themselves back in Barry's life, his friends convince him that they are needed just in time for some new oddities to befall Central City. The first of these is an apparent doppelganger for a recently deceased man. Dubbed Atom-Smasher (Adam Copeland, Haven, WWE), this new metahuman absorbs radiation to grow and become stronger. When beaten, the villain gives a cryptic message saying someone named Zoom sent him after The Flash. What Flash and his friends soon learn is that the singularity tore holes in the fabric of the universe between their Earth and another one.
Barry and friends end up with a new colleague in Jay Garrick (Teddy Sears, Masters of Sex), The Flash from Earth-2, and while the Crimson Comet has lost his connection to the Speed Force, he does tell everyone about Zoom (voiced by Tony Todd, Candyman), an evil speedster that wants to be the fastest person across all worlds. After taking Garrick's speed, Zoom has started sending Earth-2's villains across the breaches in order to kill Barry, and while many early episodes this season have the monster-of-the-week feel to them, events quickly build up to Zoom making his appearance and the team finding out exactly what they are up against.
Earth-2 sends over another ally as well. The Dr. Harrison Wells of that world steps into Earth-1 and vows to take down Zoom, even if that means reluctantly working with The Flash. Why? Because Zoom has Wells' daughter, Jesse (Violett Beane). Given what happened last season with the man they thought was Wells, it shouldn't come as a surprise that Barry has some trust issues, and that goes for both new Earth-2 colleagues.
A lot happens this season. For one, Joe gets a new partner in Patty Spivot (Shantel VanSanten), a driven policewoman who has a personal grudge against metahumans, and given Iris' lingering feelings over the loss of Eddie, Barry decides to pursue a relationship with Patty. Speaking of Iris, her mom, Joe's former wife, shows back up and tells the two that she is dying. Iris, mad at Francine (Vanessa Williams) for abandoning the two of them all those years ago, digs deeper and finds out that when Francine left, she was pregnant. About halfway through the season, we meet Joe's long-lost son, Wally West (Keiynan Lonsdale), a young guy who seems to have a need for speed.
This season also introduces Jefferson "Jax" Jackson (Franz Drameh), who ends up being Dr. Stein's missing half, not only allowing Firestorm to be created again, but also stopping an illness that is attacking Stein because of his separation from Ronnie. Another new character is Lewis Snart (Michael Ironside), father of both Leonard Snart/Captain Cold (Wentworth Miller, Prison Break) and Lisa Snart/Golden Glider (Peyton List).
Several of these events, including the introduction of Kendra Saunders (Ciara Renee), lead up to the Flash/Arrow crossover event that spins off the newest Arrowverse series, DC's Legends of Tomorrow. Kendra finds out that she is actually an ancient Egyptian priestess who is constantly reincarnated. Imbued with hawk powers, she is forced to find her love, who also gets reincarnated, and face an immortal villain by the name of Vandal Savage (Casper Crump). While the crossover event puts a temporary stop to Savage, Kendra, Captain Cold, Mick Rory (Dominic Purcell, Prison Break) and a few characters from Arrow are whisked away for a new adventure in the spin-off series.
While the setup for that spin-off is a point of interest in The Flash: The Complete Second Season, it's only a brief pause during the much bigger fight against Zoom. The events surrounding this newest menace will cause Barry to go up against yet another speedster by the name of Trajectory, face off against a time-traveling Reverse-Flash from before he went to stop Barry from becoming The Flash, and even take on Earth-2 versions of Cisco, Caitlin and Linda Park. In fact, in a two-part episode, Cisco and Barry will travel to the Art-Deco-decked-out Earth-2 in the hopes of finding out more information about Zoom and, hopefully, freeing Wells' daughter. Seeing alternate versions of many of the main characters is interesting, but Earth-2 ends up being a very different place than the world Barry is used to.
Henry Allen (John Wesley Shipp), Barry's dad, ends up making quite a few appearances this season. In the first episode, Barry is left a message from the now deceased Reverse-Flash (still in his Wells disguise), confessing to the murder of Barry's mother. With that tape in hand, Henry is released, but citing the need to give Barry the space he needs to continue to grow, he doesn't stay around too long. Henry does make several key appearances throughout the season though, giving Barry just the advice he needs to take on Zoom.
There are quite a few interesting one-off episodes. In one, Barry decides to travel in time in order to get advice from Reverse-Flash on increasing his speed. Barry has to convince the Wells/Eobard of that time that he is the Barry from that time, and not let on that he knows Eobard's true identity, all the while taking on the enemy that The Flash was facing, Hartley (Andy Mientus). In another episode, Barry faces off against the anthropomorphic great white King Shark, and in yet another, Grodd returns and kidnaps Caitlin since she was the only one who was ever nice to him. Barry will also hunt down a villain that slows down time, The Turtle (Aaron Douglas, Battlestar Galactica) and even end up in the Speed Force itself in order to have more than one introspective conversation.
While this season of The Flash is packed with a ton of events, the discs of The Flash: The Complete Second Season are even more stuffed with extra features. There are featurettes concerning the relationship between Barry and Iris, one on Jay Garrick's helmet showing up in the previous season's finale and another on Lewis Snart. There's a featurette on the Firestorm character, another on Grant Gustin's screen tests with Emily Bett Rickards (Arrow's Felicity), and one focusing on the three actors that portrayed Zoom, Tony Todd (voice), Stuntman Ryan Handley (body while the mask is on) and ... well, that would be a spoiler wouldn't it.
This release also comes with deleted scenes, a gag reel and two panels. One is the 2015 PaleyFest panel (which apparently occurred about halfway through Season One based on what was discussed) and the 2015 Comic-Con panel. There is also a featurette focusing on the Christmas episode where Weather Wizard (Liam McIntyre) breaks Captain Cold and The Trickster (Mark Hamill) out of Iron Heights for some seasonal hijinx.
There are also two special features focusing on Kendra's character and how that leads up to DC's Legends of Tomorrow. Both are interesting, but it should be noted that these same special features are also on Arrow: The Complete Fourth Season, so if you picked up that set, you will see these featurettes there as well.
Interestingly enough, that's only about half of the special features The Flash: The Complete Second Season offers. There are almost a dozen featurettes focusing on the visual effects of the series. These cover everything from The Flash digital double, to designing King Shark and Grodd, and even designing Earth-2 itself. There are featurettes focusing on specific episodes like "Fast Lane" and the season finale, as well as those that focus on the designs of various villains and their powers. These featurettes are scattered across the release's four discs and typically placed on the same disc as their focus, but I would still recommend waiting until you are done with the season as a whole before going through all of these. I feel like there were a couple of minor spoilers that were mentioned in earlier discs.
The last special feature focuses on the episode Kevin Smith directed. Clocking in at 50+ minutes, "Chasing Flash" is all about how much of a fan the director/writer/actor was of the show and everything involved with his directing of "The Runaway Dinosaur," the season's 21st episode. Everything from Smith's directing style, to the cast and crew's opinions about him and what it is like to work with Smith is explored in depth during this featurette.
Given how great this season is and the sheer amount of special features jammed into this release, I have to recommend not just watching The Flash: The Complete Second Season, but owning it. If you are a fan of the show, then this is a season you won't want to miss, and the extras, both in quantity and quality, will give you a lot of bonus insight into the series.