Things are pretty grim as we head into the season 2 finale of The CW's “DC's Legends of Tomorrow.” Captain Cold's just iced Vixen, and Reverse Flash has destroyed the Spear of Destiny, trapping our heroes in an altered reality where they have no powers.

In desperation, the Legends will devise a plan to restore everything back to normal. The only problem is, said plan involves breaking one of their cardinal rules about time travel – consequences be damned.

RELATED: Legends of Tomorrow Promises Multiple Deaths in S2 Finale

Ahead of the Season 2 finale, executive producer Phil Klemmer spoke with CBR about the Legends’ last resort, how power can corrupt even heroes and setting up Season Three in the finale.

CBR: The odds seem pretty stacked against the Legends. What's their next move? How can they fix things?

Phil Klemmer: We platform them to do the one thing they’ve been told never to do – going all the way back to the pilot when the team learned the hard lesson of why you can’t go back and undead somebody that is dead. For us, it was an important way of keeping the show engaging and trying not to give ourselves a “Get Out of Jail Free” card any time something goes wrong. Once you tell the Legends they can’t do something, that’s a fairly certain way to make sure they do it.

At the same time, we want to make it as terrible and catastrophic as Rip made it sound. This finale is supposed to be the culmination of Season 2. It’s our Legends and the Legion coming to a final reckoning. More than that, it’s meant to be a jumping-off point for the next season. It’s meant to upset the dynamic of the show in a way that makes Season 3 feel as drastically different from this season as this season felt from the last.

We didn’t want there just to be a “period” at the end of the season; we wanted this to be an exclamation or question mark. When we write 301, we want it to be like 201. We had the JSA and these new characters and villains. We want the show to continuously evolve. We didn’t want next season to feel like 2.5. We wanted to change things in a way that made it impossible for us to ever go back.

The heroes journey to 1916 where they encounter their past selves. What's so fun about having two sets of Legends?

What’s not fun is having to shoot it. When you have to do motion control/motion capture and have to force all of your actors – who are already worked to the point of exhaustion – having to act in a scene with themselves at 4 A.M. after a 12-hour day, you can understand why an actor might be inclined to tell a writer to, well, fill in the blank. It’s enormously challenging. Writing an ensemble show, where you have a cast as talented as ours, there’s never enough pages to go around. You could write scenes that last entire acts. You just have to be ruthlessly efficient with your stories, so when you double that, and then add our delicious villains and guest-stars, it’s a struggle to fit everything in.

The Legends are hoping that by preventing the Legion of Doom from ever obtaining the Spear of Destiny, somehow they can bring Vixen back to life. How tempted are they to rewrite their own histories or resurrect other loved ones?

That’s a huge component. "Legends" has a lot of mind-bending moments in it, but, yeah, that factors heavily into the finale. Everybody is left with a lot of “what ifs.” The wonderful thing about having this mystical object is, it’s like the Holy Grail in the Last Crusade, where only the pure of heart can wield it. It’s a huge question mark, because none of the surviving Legends are wholly pure of heart. They're all a little broken. The question then becomes, “What would happen if Mick Rory uses the Spear? What would happen if Sara Lance uses the Spear?” They all have their human failings; it’s what is very endearing about them. It’s what makes them Legends. At the same time, it makes it very dangerous when they are tempted to pick up the Spear and try to change history for themselves.

At the end of the day, assuming that good conquerors evil, what are the consequences of the Legends’ drastic actions?

In a way, the Legends are always going to be their own worst enemies. There will always be villainous forces in our universe. The more interesting things are the self-inflicted wounds. Everybody can relate to that, when you know what the right thing to do is, but you can’t help doing other wise. In their own hearts, they are pure. You will do something for the people you love, even if it’s wrong. That’s what sets our show apart from other superhero shows. In “Legends,” they are so human.

Season 2 was basically predicated on something they did wrong in Season 1. They blew up the Time Masters and eliminated a law-enforcement body that was probably much better equipped to do the job that the Legends end up inheriting. You will see in the finale that it’s an amplified version of that. The longer the Legends are traveling through time, well, you have these bulls in a China shop. Everywhere they go, they break things. Their intentions are usually noble, but they can’t help but make mistakes along the way. It’s like they get deeper and deeper into debt. The more they try to help, the more they realize there is more work to be done. They’ve broken more than they’ve fixed.

This show was designed to feature a rotating roster of heroes. Throw us a bone. What DC characters are at the top of your wish list for Season 3?

I can’t name names.

How do you determine which characters to incorporate? Do you flip through Who’s Who in the DC Universe or does it boil down to story?

The question we always ask ourselves first is, “How do we want to change the dynamic?” We have the characters that we know and love, and we’ve spent two years getting to know the core of them. Obviously, we’ve gotten to know Nate and Amaya very well this past season.

For me, it’s always taking a character who has gotten to a place of complacency or comfort or you feel like you know who they are – and then it’s introducing a character who is going to change that person. “Legends” is basically a story about a dysfunctional family who are stuck on a spaceship traveling through time. You never want them to find their natural angle of repose, where everybody knows what their job is and everybody knows what their dynamic is. Our show lives on its unpredictability. When we think of characters we want to bring into the show, we start with the characters we already have and then reverse-engineer a character who could have the most impact or provide the most friction or mystery. Then, once we start to know the human version of these characters, only then can we start talking about which superheroes could provide the best foil for our existing Legends.

“DC’s Legends of Tomorrow” stars Brandon Routh as the Atom, Victor Garber and Franz Drameh as Firestorm, Caity Lotz as White Canary, Dominic Purcell as Heatwave, and Nick Zano as Citizen Steel. The finale will not air at its regular time, but will instead air Tuesday, April 4th at 8:00 EST on The CW.