Reviewed by Louis Rabinowitz.

We may be a good three weeks into 2016, but there’s still plenty of time to make some New Year’s Resolutions for the year ahead – a goal to improve your life in the following twelve months. As The Flash’s return showed, Barry Allen certainly came up with a pretty huge resolution – but, like pretty much all resolutions, things didn’t go exactly to plan and everyone involved was left with the opposite of fulfilment.

The mid-season premiere, Potential Energy, revolved around Barry’s deliberations over telling Patty his secret identity at the risk of Zoom finding out and killing her. The Flash rarely peaks with its premieres, so it wasn’t surprising that Potential Energy was fairly middle of the road – but, considering The Flash’s standards, it was still a decent return. Interestingly, it’s the central storyline here that’s probably weakest, with the strongest material to be found in the subplots and comic-book action elsewhere. Grant Gustin and Shantel VanSanten are undoubtedly talented actors, and the Barry/Patty material is competently written, particularly considering it pivots around one of the strongest elements of the mid-season premiere, the villain (but more on the Turtle below). Indeed, there’s even a couple of moments where the storyline really sparks, such as the effectively jolting cold open in which Barry experiences a nightmare of Zoom killing Patty, and a scene between Barry and Iris that continues to illustrate how their increasingly mature and refreshingly honest friendship is fast becoming a stalwart element of the show. And, on the whole, the fact that Barry’s secret-keeping is being portrayed as genuinely destructive and self-harming, damaging his relationships with friends on the basis of mere paranoia is a solid one that shows that the writers at least know what they’re doing with Barry’s secret identity as a plot device. If The Flash had stuck the landing with an ending that either delivered a powerful twist or a heart-warming affirmation of Barry and Patty’s relationship, then the Barry/Patty storyline would have been a general success.

Unfortunately, right at a crucial moment in the Barry/Patty storyline, Potential Energy fumbles the catch, which only exacerbates the flaws throughout the rest of the episode. Ultimately, despite the underlying competence of it all, Potential Energy is on well-trodden ground here – part of the fun of The Flash is its fun, heartfelt takes on cheesy old superhero tropes, but the wholesale usage of typical secret identity clichés from other works of superhero fiction is a little grating. These plot beats have been played out before many times in other movies and shows, and, furthermore, the usage of these old ideas feels like a true waste of potential – the Barry/Patty storyline could have played out as a refreshing subversion of these tropes, providing a more mature and streamlined slice of secret identity drama that would have attempted to change up the tired old clichés utilised here instead of simply rehashing them. As mentioned above, the generic nature of this plotline wouldn’t have been much of an issue if Potential Energy had ended on a high note in this regard – instead, in an attempt to show the consequences of Barry’s actions in a major way, The Flash overplayed its hand with a twist that simply felt unsatisfying to watch.

The narrative intention behind Patty’s departure is understandable, and her departure from Central City is preferable to the other option (Patty getting fridged in a similar way to the nightmare scene at the start of this episode), but it’s a development that plays out far too quickly to work. It’s the moment the entire episode is building up to, but the rushed nature of it all makes it feel like The Flash is just hurrying to get Patty out of the way in order to move onto other plotlines – and while those other plotlines may be fun, Patty has been built up considerably over these past 10 episodes, so an exit as flat and garbled as this left this crucial plotline feeling somewhat deflated as a whole. I hope we’re not done with Patty, because this would have been a thoroughly disappointing end for a likeable, charming character.

Elsewhere, Potential Energy generally does a solid job. Another major character conflict this episode is Joe and Wally – and it’s abundantly clear from the off that The Flash is going for a slow burn with Wally, gradually reconciling him with Joe and Iris before the show even starts to think about making him into the Kid Flash, the superhero he’s essentially destined to be (considering that Wally seems to be the Roy Harper of this show, season three is a good bet). That means that Potential Energy is merely laying the groundwork for the drama to come – but it does so effectively, introducing an iteration of Wally who is the hero of his own domestic story, looking after his sick mother and harbouring a hell of a lot of resentment about his supposedly resentful father. It’s an interesting, bold route to take with the character, and there’s rich potential here for a fascinating character study of a son who grew up in his own world, resentfully entering a completely different world with a father who never knew him. Potential Energy stumbles a little with the moment where Wally agrees to stay and eat dinner, which feels like an unnaturally rushed development that slightly undercuts some of the material that came before, but this is an encouraging start for Wally with plenty of promise for the future.

Earth-2 Harrison Wells has been one of season two’s undisputed successes, and his intriguing evolution is making him into a wildcard figure who is almost as fascinating as his evil Earth-1 counterpart. Potential Energy managed to quickly assuage my concerns about the show retreading last year’s ‘evil Wells’ story due to his alliance with Zoom by making it abundantly clear that Wells is going to considerable lengths to try and outwit Zoom, frantically trying to wriggle out of his nemesis’ grasp by working out a way to finally defeat him. Tom Cavanagh nails the character’s understated desperation and crippling fear of Zoom here, continuing to add layers to a character who can spin on a dime from amusingly cranky to compellingly serious without ever feeling inconsistent. Wells’ attempts to figure out a way to defeat Zoom also end in hugely intriguing fashion in Potential Energy’s penultimate scene which plays, cleverly, like a reprisal of last season’s ‘evil Wells’ stingers of Wells skulking about in STAR Labs generally being evil – but with this Wells, his murderous actions take on an entirely different meaning. The scene where Wells kills the Turtle is exciting for its mystery and the implication that Wells might be trying to take on Zoom himself (that’ll end well), but it’s also a fantastic character moment that turns a familiar situation from last season on its head and gives it a whole new meaning: instead of evidence of a nefarious plan, Wells’ murder is evidence of a desperate man pushed to his limits by a terrifying enemy, breaching his own moral code by seizing the one slim chance he has of escaping his tricky predicament.

Surprisingly, one of the best parts of Potential Energy is the villain of the week, the Turtle. With a name like ‘the Turtle’, it’s easy to assume this would be the same formulaic villain of the week fare, but Potential Energy really excels with its villain by going beyond the typical formula. Instead of being just a random criminal for Barry to punch, the Turtle is crucial to both the central emotional arc concerning Patty and the season’s ongoing storyline about Zoom himself, with the Turtle’s superpowers looking like they could actually be the key to slowing Zoom down enough to defeat him. He’s not awfully complex, but there’s enough of a personality to latch onto, with an unusual late-game twist revealing that the Turtle keeps his victims frozen in cabinets, making him a hell of a lot more twisted and psychotic than your garden variety standalone villain. With some genuinely impressive, visually inventive effects portraying his powers, the Turtle is a prime example of how villains of the week can work when they function as important parts of ongoing storylines – although The Flash utilises the format less frequently nowadays anyway, it’d do well by remembering the lessons learned here.

There’s plenty of other tidbits that will presumably play out as major conflicts as the season goes on, such as the introduction of Jay’s disease that is slowly killing him – a development that finally adds a layer of intrigue to a frustratingly inert character – and that idea of seeds being laid for further conflicts just about sums up Potential Energy as an episode. There’s so much going on here, but most of it is set up to pay off later on down the line. While it’s great that The Flash is going down a more serialised route, because that means it has the time to craft a richer conflict with Zoom with considerable emotional depth, there’s a flipside to this increased level of serialisation. Just about every element introduced in Potential Energy has (ahem) the potential to develop into a compelling storyline, and there’s the seeds of some really good ideas evident throughout – but as an episode in of itself, it’s not particularly gratifying viewing in the short term. These kind of set-up episodes that don’t have much in the way of a satisfying pay-off at the end are necessary for serialised stories, but I’d have preferred the ratio of build-up to pay-off to have been shifted a little more in the direction of pay-off with a slightly more hopeful conclusion, just to make this more of an individually satisfying slice of television. Perhaps this episode will play better on binge-watches with the resolutions easily accessible – time will tell on that one.

Despite those grumbles, Potential Energy finishes on one hell of a conclusion to tide us over til next week. It’s kind of a pity that the marketing had spoiled it beforehand, but there’s no doubting how effective a surprise the sudden, inexplicable return of the Reverse Flash is. It’s the perfect curveball to end on, shaking up any visions of what the next episode could look like while providing an intriguing element of mystery for fans to dissect over the coming week – how the hell is the villain who was erased from existence back, and why is he so baffled by his surroundings? Okay, the trailers answer that one too (thanks, CW marketing department!), but the re-appearance of Barry’s greatest foe is just the burst of (ahem) energy this episode needed that sets up what could be a doozy of a following episode in style. The subtle, cryptic title of that episode? The Reverse Flash Returns…

Rating: 7/10

Potential Energy is by no means a poor episode of The Flash, but it unfortunately fumbles its exploration of Barry’s secret identity fears with a generic story finishing in an ill-advised, rushed twist. It papers over some of the cracks with compelling, emotional side stories and intriguing set-up, but this is a merely good return rather than a great one on the whole.