Time travel is a tricky trope. When you take it on, you’re committing to the idea of juggling several balls, without dropping them and without ever stopping. There’s a lot to keep track of, from the way character choices affect the past to potential ripple effects later on down the line — and lest we forget, there’s also the frequently mentioned rule that you’re never supposed to meet a version of yourself, on the off-chance you could create a rip in the fabric of time and space (thanks for that one, “Back to the Future” trilogy).

Some shows have pulled off a time-travel focus to a memorable degree — “Life on Mars,” “Outlander,” “Doctor Who” — and others have tried valiantly and failed. Over this fall season, two series have emerged as frontrunners in the genre, evidence how the concept of time travel in a television show can still be attempted, and done well.

On the CW, “DC’s Legends of Tomorrow” has made it past a rocky first season, to thrive in its second, while on NBC, “Timeless” has proven one of the most surprising success stories of the season. Both shows incorporate common time-travel storytelling elements, but differentiate enough — from one another, and what’s come before — to stand alone.

The power of found families

No time-travel story since “Star Trek” or “Sliders” would be complete without a ragtag group tasked to preserve the known timeline. In “Legends of Tomorrow,” it’s a motley crew of superheroes (remnants and castoffs from the CW’s other DC properties) who take on the responsibility as guardians of time — mostly because they blew up the original ones. After being scattered through time for their own safety, the team has reunited and promoted one of their own to acting captain: Sara Lance (Caity Lotz), otherwise known as the White Canary.

Looking at the Legends themselves, it might be tough to imagine them as friends — the group includes everyone from a partially-reformed thief and pyromaniac, to the former CEO of a tech conglomerate — but as they travel through time, encountering everyone from the Justice Society of America to famous historical figures such as Albert Einstein, there’s no question the Legends will have each others’ backs.

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On the other side of the spectrum, “Timeless” features ordinary people recruited for an extraordinary purpose. It’s a smaller team — professor Lucy (Abigail Spencer), engineer Rufus (Malcolm Barrett) and soldier Wyatt (Matt Lanter) attempt to stop a villain from rewriting the history of America — and as in “Legends,” the de facto leader is a woman, as Lucy knows enough about each timeframe they’re in to let the others skate mostly under the radar.

It would’ve been convenient for “Timeless” to fall into the predictable trap of turning its characters on each other — early on, the show sets up the twist that Rufus is spying on Lucy and Wyatt for his employers; each teammate’s connection to the team’s nemesis Garcia Flynn (Goran Visnjic) continues to unfold — but in Rufus’s case the secret is discovered quickly. Rather than its main trio wallowing in betrayal, the show lets these characters to grow closer in the midst of a bigger threat.

A greater conspiracy looms

The main problem “Legends of Tomorrow” had in its first season was the fact that it took so long for our heroes to finally stop their Big Bad; in a few too many episodes, Vandal Savage (Casper Crump) oh-so-conveniently slipped through the Legends’ grasp. Thankfully, the show dropped the Savage arc and started anew in Season 2, giving the team some fun on a week-to-week basis while correcting problems created by nameless time pirates. Based on where “Legends” is headed, though, audiences can expect a somewhat larger arc. The villains of season 2 might look familiar to viewers of “Arrow” and “The Flash,” but it already looks like our heroes might have a partial leg up on Damien Darhk (Neal McDonough) and Eobard Thawne (Matt Letscher).

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Timeless fans are still mulling over the origins of the shadowy organization Rittenhouse, which was name-dropped early on but still continues to leave narrative breadcrumbs as the season progresses. Thanks to recent developments, it’s been revealed that Lucy’s father is a Rittenhouse agent — and everything we’ve seen so far would seem to imply that Rittenhouse is the real villain of the season. After all, the group has been behind not just blackmailing Rufus for info on his fellow time-travelers but the death of Flynn’s family, prior to the events of the series. By brutally reframing Flynn’s actions in a different light, and revealing that a future version of Lucy has been helping him all along, the show proves it’s using the great legacy of time travel, and all the mental acrobatics it can inspire, to greatest effect.

“Timeless” airs Mondays at 10:01 p.m. ET/PT on NBC; “DC’s Legends of Tomorrow” airs Thursdays at 8 p.m. ET/PT on the CW.

Posted by:Carly Lane

Carly's the weekend editor of The Mary Sue and co-host of Supergirl Radio. Bylines at Teen Vogue, HelloGiggles and The Toast, among others, mostly on pop culture and geeky things.