The Flash: 10 best episodes, ranked

3. “Enter Flashtime” (Season 4, Episode 15)

There’s a strange irony in the fact that, in a season where The Flash was trying to distance itself from its sole focus on speedsters, its best episode was one that took place across milliseconds as multiple speedsters tried to save Central City from imminent destruction.

As that sentence alone indicates, the stakes for “Enter Flashtime” were incredibly high from the offset, as Barry wasn’t able to prevent the detonation of a nuclear bomb, forcing him to have to act fast – faster than he had ever acted in his life. With the help of Jesse Quick and Jay Garrick, he had to think on his feet and figure out how to save his loved ones before they were wiped from existence. And that’s where the season’s neat new trick, Flashtime, came into play.

The show made 40 minutes last a lifetime in the best possible way, throwing obstacle after obstacle in the Scarlet Speedster’s way that left us all feeling like a standalone episode in the middle of the season could actually carry some emotional weight. And it did, for a Flashtime conversation with his “lightning rod” Iris set the stage for an emotional, hard-fought sprint to victory for the man of the hour (or many, many milliseconds).

Tense, powerful, and gripping the whole way through, “Enter Flashtime” was a welcome change-of-pace in a convoluted season that stood out as a reminder of what The Flash was capable of whenever it carried real stakes. It’s still an edge-of-seat thriller with more rewatch value than the rest of the season combined.