Firefly Lane: Sarah Chalke Answers All Your Questions About That Series Finale

The final episode opens with Kate and Tully talking in the mirror before Mara's wedding starts in 2016. Thanks to the voiceover and the dialogue, it seems like Kate survives, only to reveal that Tully was just imagining her best friend with her. How did that scene affect you?

I remember filming on that day. We're looking into the mirror, but then beyond the mirror is just ocean forever. At that point, every scene is emotional. Normally as an actor, you read your scene and think, hopefully I can cry on the day I'm supposed to cry. But this was more like, I think we have to pull it back because in this scene I should not be crying. I remember doing that scene so well.

How do you think viewers will react? 

It's going to be different for every audience member. There is that moment in that scene where all of a sudden Kate's not in the mirror and some people will have the realization then that she's not really there, or it might happen later. But I thought it was special. It was a great idea that Maggie brought Kate into that day.

Was that the most challenging scene to film? There are so many emotional ones in these final seven episodes.

One of them is the moment where Kate and Tully are in the hospital and Tully's holding on like, “We're going to keep fighting. We're doing this.” And Kate has accepted that's not going to be the case and they're holding each other in their arms.

And then when I read the letter during the funeral to Tully. It wasn't a moment where I thought that Kate should be bawling, but every time I got to the part where I was like, {Take care of Mara for me," no sound would come out. I would just start crying.

The other ones that stick out are the scene where Kate and Tully are on the balcony and Kate dies, but the neighbor who actually lives next door didn't love us filming there. I think he had access to the frequency of the walkie-talkie, so whenever they would say “rolling,” he would start up the leaf blower every single time. It's such an emotional scene, and then it's the leaf blower. It was so loud. It took a long time. Oh my god, it was so difficult.

That is so rude!

I know. [Laughs] 

Meanwhile, you brought up the letter that Kate leaves Tully that she reads outside the funeral. I thought as devastating as the ending was, having Tully dance to Abba's “Dancing Queen” was an uplifting, positive way to end the series. It's devastating, but there's also so much joy there.

Totally. The scene of Katie Heigl dancing to that at the end is one of my favorite scenes of the whole season. You don't even go into the funeral. It was such a great choice and such a unique choice. You don't even enter the doors, you just stay outside with Tully and she's dancing and so in the moment. I loved it.