Romance is a hard thing to find on The 100 (and an even harder thing to keep), but the one couple who has managed to weather apocalypses, space travel, and even hostile invaders is Bellamy (Bob Morley) and Echo (Tasya Teles).

Season 6's new planet and all its lovely (read: deadly) quirks will test every relationship on every level though, and only time will tell if Becho can make it out the other side. Teamwork and compromise are going to be key in this dangerous new journey, but at least it sounds like those are two things Becho has got on-lock heading into Season 6.

"In Season 6 we're going to see the two of them — they worked together well as a pair," Tasya Teles told reporters last fall on the set of The 100. "We're going to definitely explore that relationship but we also are going to see more of how the relationship strengthens each of them and what is it that each provides to the other within that. But they operate as a great unit."

Unity aside, the one person who has presented a major roadblock in their romance (and likely always will) is Bellamy's sister, Octavia (Marie Avgeropoulos). Ever since she and Echo fought to the death, which ended with Echo tossing Octavia off a cliff, the younger Blake sibling been... less than warm to her brother's girlfriend. It's an understandable grudge she's holding onto, but will it eventually be an insurmountable obstacle for Becho?

Discover Your New Favorite Show: Watch This Now

"There's some lingering things [between Echo and Octavia]," Teles said. "That's a tough one. Octavia does affect Bellamy and that in turn affects Echo because she worries and cares about him. It's always going to be a tricky one for her to navigate. She's always walking on eggshells around that because it's a very — those two have such a loaded relationship, so Echo knows to not push too hard, but she does want to see Bellamy happy and in a good place."

When it comes right down to it, there are bigger issues between Octavia and Bellamy that need sorting out before we can even approach the Echo thing. There's that minor thing of him poisoning her and her throwing him in the fighting pits, after all. Still, we hope and pray for a Blake sibling reconciliation in Season 6, but that may be out of reach if Echo and Octavia can't mend the fence for Bellamy's sake.

The 100 returns Tuesday, April 30 at 9/8c on The CW.

(Disclosure: TV Guide is owned by CBS Interactive, a division of CBS Corporation.)

PHOTOS: The 100 Season 6 Premiere Photos

Tasya Teles and Bob Morley<em>, The 100</em>Tasya Teles and Bob Morley, The 100