Grey's Anatomy: Ellen Pompeo, Kelly McCreary and Martin Henderson preview love triangle

Alex will be facing the consequences of his actions during Thursday’s episode of Grey’s Anatomy, but the real drama comes via Meredith (Ellen Pompeo), Maggie (Kelly McCreary), and Riggs (Martin Henderson) as they navigate their accidental love triangle.

During the season 12 finale, Maggie revealed to Meredith that she had feelings for Riggs, completely unaware that her half-sister had already slept with him. In the premiere, Maggie subsequently made Meredith swear never to lie to her again after discovering she lied about Alex’s role in what happened to DeLuca (Giacomo Gianniotti). “She really can’t betray her sister again,” Pompeo tells EW. “Yet she’s finding herself in this triangle that Maggie for sure is going to see as a betrayal.”

Maggie’s feelings will actually help Meredith keep Riggs at arm’s length for the time being. “She actually is using it as an excuse to not have to deal with Riggs,” Pompeo says. “But she’s also choosing not to tell her sister that she’s already had a fling with Riggs, which of course Maggie is going to see as a betrayal. Meredith sees it as protecting her and doesn’t want her sister to get embarrassed.”

However, “Riggs doesn’t know that the Maggie situation is complicating it,” Henderson says. “The audience does. So we see Meredith trying to protect Maggie’s feelings and also deal with her own or come to terms with what they may be. As far as Riggs is concerned, there’s this great attraction, and he hasn’t felt anything for anyone like this for a long time. So he’s like a bull at a gate. He’s ready to go back to the parking lot, as it were, and Meredith is turning him down consistently. However, there’s still sparks flying in unguarded moments that confirm for Riggs that this is actually something more than just the sex that happened at the end of last season; it’s actually a true connection that he wants to really build on. But her resistance and reluctance, Riggs initially interprets as her just maybe needing a little more time or a little space.”

Therefore, the more Meredith pushes Riggs away, the more he thinks she’s just playing hard to get. “He uses that to prove his point, that that’s because she wants him,” Henderson says. “‘You want me to say no because you want me,’ which infuriates her more, but she’s not entirely saying no. She’s caught between a rock and a hard place.”

Keeping this secret from her sister will likely end up blowing up in Meredith’s face. “I would think there are going to be repercussions,” Pompeo says. “Eventually Maggie’s going to find something out.”

“It’s going to definitely be way worse because she makes Meredith promise never to lie to her again, and whatever Meredith’s motivations for doing so, she ultimately does,” McCreary says. “Trust is a really, really important issue for Maggie. We saw how she reacted to Richard holding back the truth from her when she first arrived at the hospital, and it affects her very deeply when people are not completely transparent with her. She’s invested so much in creating a bond of trust with Meredith and invested a lot in creating this new family with her, and part of that investment has been bearing her soul. When you find out that someone hasn’t been truthful with you, you regret having shared that, and you have to reevaluate how close you want to be to that person.”

Through navigating the love triangle, viewers will also learn much more about Riggs. “When the relationship actually really starts to happen, whether it’s with Maggie or Meredith or both — I’m kidding — whoever it ends up being with, that’s when we’ll start to see a little more of his inner emotional life,” Henderson says. “At this point, he’s kept quite a bit of a mystery, and of course, last season was all about, ‘Well, do we hate him? Do we like him? Is he a good guy? Is he a bad guy? What really happened with Megan in the past?’ I’m hoping that this season will actually start to shed more light on his real character as he becomes intimate with someone in the hospital.”

Whomever Riggs ends up with, Henderson teases that he’s been working much more with Pompeo this season. “We were kept quite separate in the first season that I was in, last season,” Henderson says. “I’m really enjoying just connecting creatively with Ellen on screen, and I think we work really well together. It’s always fresh and fun.”

Grey’s Anatomy airs Thursdays at 8 p.m. ET on ABC.