The previous episode of ABC's "Grey's Anatomy" saw Callie bringing her new girlfriend Penny to a dinner party at Meredith's house.

But instead of enjoying the dinner and making new friends, the episode saw a number of relationships on the rocks when Meredith announced that Penny was the one who let Derek die.

Penny wasn't insistent on doing a test that could have saved Derek's life, and it looks like Meredith and her friends are going to hold it against her. Sadly, Penny's role in Derek's death is also going to complicate her new relationship with Callie, and the upcoming episode will see Meredith confronting Callie about Penny.

"Well first of all you have to get Callie to just figure out what's happening between her and Penny," executive producer Debbie Allen told The Hollywood Reporter about the future of Callie-Penny relationship. "At the end of the episode, Callie doesn't even give her the address to where she is. Callie doesn't know how to react. Callie feels that maybe Penny should have told her more."

Another relationship that's on shaky ground is that of Meredith and Amelia's. Derek's sister is not in a mood to forgive her sister-in-law for not immediately revealing Penny's role in her brother's death.
And their tense relationship isn't going to get better anytime soon.

"Amelia is so caught up in how she feels, she's not even thinking about what Meredith has gone through. It's family time. The people closest to you are the ones who can hurt you, misunderstand you or make it difficult. The people you don't care about, you can just walk away from it," Allen told the media outlet.

Unfortunately, the synopsis for the next episode doesn't reveal much with regards to the status of Meredith-Amelia and Penny-Callie relationships.

The official synopsis reads:

Grey Sloan Memorial not only welcomes a new transfer resident, but also a patient who's the topic of conversation after accidentally sending his sex tape to his entire congregation. Meanwhile, Richard wrestles with how to progress his relationship with Maggie when an old friend visits the hospital, and April brings in a case of a young boy from the Middle-East.

 "Grey's Anatomy" is aired Thursdays on ABC.