With all the crazy easter eggs and fan service, what really sold the episode were the emotional family moments. That is what grounds the great alternate reality/ time travel stories. The writers of The Flash are rock solid.

Heatwave the head of the fire department.

Shouldn't it have been the Superfriends on Jay Garrick's speed dial though?

The whole cast must have had the time of their lives playing their Earth-2 alter egos.

They compressed 5 hours worth of stories into 1 episode. Just crazy.

Loved the Bonnie & Clyde thing Killer Frost & Deathstorm had going. Well, while it lasted.

Or I thought they were going to do the "For The Man Who Has Everything" ending…

Plus Benoist acting as Hank acting as Kara. Head movements and everything.

Did anyone else think it looked like they let the Black Mercy slither away? Lord kind of a gave it a "OH YOU!" smirk as it slowly escaped.

No spoilers, but did anyone else watch ep4 on CTV after the Super Bowl? Snart is BOSS. This episode is going to be a fangirl favourite for the ages.

Great ep. Maybe the Legends of Tomorrow people already planned that, but Doctor Who beat them to the punch and they had to change things awkwardly.

The Canary and Cold Comedy Hour

Canary x Cold??

Now that this show has done it, I hope they never bother with that Fantastic Voyage remake.

I Know What You Did 20,000 Leagues Ago?

The Beast from 20,000 Fathoms?

"20K SLUTS" is the porn parody.

Maybe this is secretly that League of Extraordinary Gentlemen reboot they're working on.

Indeed, check out Hawke's AMAs on Reddit. He comes across very down-to-earth and intelligent.

Singer could film the Archimedes story, just for the bathtub scene.