Our double-episode Casualty special for its 40th anniversary is now streaming on BBC iPlayer, and I'm still recovering from the emotional whiplash.From the hospital explosion in its opening minutes, the drama is operating with a full-force gusto we've rarely seen in the show. There's no longer one main storyline with smaller ones unfolding in the background — which is the usual Casualty format — but a gigantic story that involves absolutely everybody.Nobody is overlooked or left behind, and all cylinders are firing. Whether we're in the heart of the hospital with Dylan (William Beck) as he struggles with the overwhelming influx or patients, or outsourced to makeshift emergency rooms with Flynn (Olly Rix) and Stevie (Elinor Lawless), the intensity never lets up.But even with all of this chaos going on, I can't help but think that Flynn and Stevie would make a beautiful couple... if it was something that they wanted.With an underlying tension already between them, is this something that we're ever going to see? If Rix's response is anything to go by, we can remain cautiously optimistic. 'There is a real depth to their relationship'"To some extent, the answer to that is quite a simple in that it's not my decision," Rix explains. "That's one for the producers. But I think there's something there that they're the last to see. "The audience has seen it. The producers and the writers have seen it. I think it's sort of been there from the off, and it's taken a moment like this to reorientate them, and perhaps to get them to realise that there is a real depth to that relationship. I think there's a lot more to come... I'll say that much."I think Rix is right. There's nothing quite like a life-risking tragedy to bring two people together in a way they've never been before — I mean, how many romantic dramas have based their premise on this exact idea?The truth is that if Flynn and Stevie do end up together, their romance will likely be incredibly drawn-out, leaving us kept waiting for the slow-burn to materialise into something more.For now, at least, we've got the great chemistry between the two actors. "Ellie and I work very nicely together anyway and we've always improvised well," Rix adds. "We're quite free in the way we do scenes together, and that was encouraged and embraced in the filming of these specials. I had a great time. I hope it shows."