After planting seeds from the very first episode, the time has come for The Flash to deliver on the mystery surrounding Ronnie Raymond’s fate the night of the S.T.A.R. Labs disaster. The result is a twist that closes as many wounds as it reopens, while the episode ensures that a brand new metahuman can’t steal the spotlight from the series’ star – and the mysterious murder that set him on his present course.

In “The Nuclear Man”, written by Andrew Kreisberg and Katherine Walczak, Ronnie Raymond (Robbie Amell) – the former fiancé of Dr. Caitlin Snow (Danielle Panabaker) – is revealed to be lost within his own body, now controlled by Dr. Martin Stein (Victor Garber). As the S.T.A.R. Labs team seeks to separate the two safely, Barry (Grant Gustin) attempts a new romance, and Joe (Jesse L. Martin) works with Cisco (Carlos Valdes) to find new evidence in the murder of Nora Allen – with a startling conclusion.

Even with so much heavy material to cover, the episode reminds viewers that Central City is never too dark, with a hero for whom deciding on an outfit for his date is a taller order than running into a burning building in search of trapped occupants.The dating game may seem like small potatoes compared to the episode’s more epic sequences, but the show’s knack for juggling a wide range of subplots (while making all seem equally relevant) is once again on full display.

Thankfully, less is once again more when it comes to the potential love triangle between Barry, Iris (Candice Patton) and Linda (Malese Jow); the unrequited/denied feelings between Barry and Iris are cashed in immediately, allowing the former to put his romantic past behind him in so genuine and healthy a manner, Oliver Queen would be wise to take some pointers. After all, ‘The Nuclear Man’ has bigger fish to fry.

Actor Robbie Amell had but a single episode to establish the playful relationship between Ronnie and Caitlin, accomplishing the feat as well as could have been expected. His new form, however, demands something else entirely. Dr. Martin Stein (the other half of Firestorm) makes his first appearance, cleverly delivered in a flashback to Barry’s day leading up to his own date with destiny, but soon hands Amell double-duty: portraying not the lovable Ronnie, but the unbalanced – and later all too self-aware – Stein.

The resulting performance (read: impersonation) is nowhere near as charming as Caitlin’s charming fiancé, and likely deliberately so. Without knowing how the two personalities will be handled in the future (and there will be a future, despite what the episode’s conclusion may imply) it’s hard to determine the pros and cons of adding yet another brilliant mind to the already academic cast. Yet the confirmation that there is more to Firestorm than Amell alone holds promise – and the special effects sequences the character brings with him are likely to sway even the less enthusiastic.

The arrival of Firestorm was long advertised, since the addition of a new DC Comics superhero is a headline in itself. But this is The Flash‘s show, meaning the progress into Joe’s off-the-books investigation of Nora Allen’s murder may haver the biggest impact on the cast going forward. It also offers a chance for Joe and Cisco to combine intellects (and inner children) for a worthwhile cause, and, no surprise, the chemistry between the two is a welcome addition.

Their conclusion that one of the two speedsters present during the murder of Barry’s mother was, in fact, Barry is something we’ve suspected since the series premiere (and believe is just the tip of the time travel iceberg). Even so, the methods through which the duo arrive at that same revelation are well conceived and executed – and Joe’s decision to reveal his prime suspect to Cisco gives the typically-lighthearted character another layer to develop in the coming weeks.

To prevent the show’s many cast members and conspiracies from seeming too clearly-defined, Harrison Wells’ decision to throw caution to the wind and attempt to save Ronnie and Dr. Stein’s lives (for which he takes personal responsibility) further clouds his motives and overall endgame. In addition, both Martin Stein and Ronnie Raymond will have a new pursuer to escape when General Eiling (Clancy Brown) returns to Central City.

Progressing those two storylines simultaneously may seem a tall order, but this week’s episode managed the challenge well enough. The good news: the coming weeks should pack plenty of action on the Firestorm side (before a rumored return near the season’s end) as well as world-changing revelations and time travel – as Nora Allen’s murder continues to unravel.

The Flash returns next Tuesday with “Fallout” @8pm on The CW. Check out a preview of the episode below: