Ever since Agents of S.H.I.E.L.D. debuted back in 2013, it’s been hard to think of Fitz or Simmons as two separate beings. Back during season one, they were the quirky science duo that added a bit of lightheartedness to the series, and then Ward dropped them in the ocean, forever altering their relationship going forth. In season two, we saw Fitz & Simmons go through a bit of a rough patch, only to come back for the show’s third season stronger than ever, something that was more than evident during this past Tuesday’s episode, “Chaos Theory”.

Now, it looks as though their relationship is finally taking the next step. After years of waiting for it to happen, Fitz & Simmons will see their relationship change from a platonic one, to something more per showrunner Jed Whedon.

“Their relationship will visibly change forever,” executive producer Jed Whedon tells EW. “Their chemistry is something that was conceived, in creating the characters, as two people who are inseparable. We talked about many different versions of that before casting it — they’re like brother and sister who are always bickering and they complete each other’s sentences, drive each other crazy and are totally co-dependent.”

For many fans of the series, finally seeing these two characters take that step, after finally coming to terms with their feelings for one another is an exciting prospect. Especially considering these two team members have arguably been through some of the worst predicaments over the course of the series. (Seriously, can we have a season finale where something terrible doesn’t happen to them, writers?)

“For a while, that was the beautiful thing about the FitzSimmons love story is that, to everyone around them, it’s so clearly obvious that they should be together, but to Fitz and Simmons, it seems like the most absurd idea ever to be anything beyond friends, working partners and each other’s best friend,” Tancharoen says.

Of course, being that this is Agents of S.H.I.E.L.D. we’re talking about, things won’t be easy for FitzSimmons. After all, they still have to try and rescue Will.

“We always have to keep it complicated,” Whedon says. “And we continue to do a good job of that moving forward.” Case in point: The rescue mission for Jemma’s off-planet fling may dampen the honeymoon period. “This is the episode where they both will express their feelings finally about everything that’s gone down,” Whedon teases.

Be sure to catch the eighth episode of season three, “Many Heads, One Tale”, this Tuesday on ABC at 9 PM EST.

Source: Entertainment Weekly.