Warning: This post contains spoilers fromThe Flashs 100th episode, which aired Tuesday night.
Read at your own risk!
A familiar character made a surprising return inThe Flashs 100th episode.

Credit: Jeff Weddell/The CW
Who is she working with?
We had, actually, a wildly different version of season 5 at the midpoint of last season.
Youll really get to see the relationship moving forward in the back half of the season.

Jack Rowand/The CW
How would you describe their relationship?I would describe it as hes her coach.
One of the questions weve had all season is how Nora learned to use her speed.
At the beginning of the season, I sawa theorythat Thawne was behind Noras arrival.
I wasnt really surprised, but I was surprised by one section about what I read.
Was Cicada part of Thawnes plan along?
Cicada always existed, but like we explained, not that version of Cicada.
So the reason for that is going to play into the back half of the season.
Team Flash failed to defeat Cicada in the episode.
CCPD is brought into the fold, so hes a wanted man.
Ill just say that this is sort of our act two.
Hes more concentrated on stopping Team Flash than he was initially.
Sherloque is getting closer to figuring out whats going on with Nora.
Hes starting to slowly put these pieces together.
Hes going to run into a couple roadblocks.
You sort of start to feel for the guy.
I think your natural inclination is to protect your children from some of this stuff.
The way that Jessica played that, I think, was just perfect.
But yeah, I think she just has a really complete picture of who her father is.
Its hard with episodes like this when you have 42 minutes to tell the story to get everybody back.
There are scheduling conflicts.
I think we wouldve loved to have a longer scene with [Teddy Sears] for sure.
We wouldve liked to get Tom Felton back, that wouldve been great.
Patty Spivot [Shantel VanSanten] wouldve been great.