'The Flash': Iris' Bachelorette Party Gets Crashed In "Girls Night Out" Clip

The CW has released a clip from 'Girls Night Out,' the upcoming fifth episode of The Flash's fourth season.

The scene sees the ladies of Team Flash joined by Arrow's Felicity Smoak (Emily Bett Rickards) as they have what is supposed to be a low-key bachelorette celebration of Iris (Candice Patton) ahead of her wedding to Barry (Grant Gustin.) However, the ladies' classy girls' night out takes a turn when someone from Caitlin's (Danielle Panabaker) time as Killer Frost shows up to collect her for her former boss, Amunet.

Of course, Felicity and the others mistake the visitor for a stripper considering the occasion, but when the man drops his eye into a glass of champagne instead of dropping his pants, the ladies realize that he's not the entertainment and this party is about to take an unexpected turn.

With Caitlin's time away from Team Flash coming back to haunt her, the episode will also see her relationship with Iris take a turn as well. Patton revealed earlier this year that Iris and Caitlin's friendship will develop further this season, adding to The Flash's female dynamic on the show.

"We're definitely going to see Iris' relationship with Caitlin especially develop this season, which we haven't seen before, which will be really nice for fans," Patton said.

Also, nice for fans will be getting to see more of Killer Frost. Panabaker previously told ComicBook.com that Caitlin's alter ego's story plays a part this season.

"Fans who love Caitlin Snow won't be disappointed and fans who love Killer Frost won't be disappointed," Panabaker said. "One of the things I wanted explained last season that I don't know was ever totally clear, and I don't know that we have the answer yet, is why Killer Frost is evil. I'm not totally sure why everything she does causes the physical body of Caitlin Snow to act so badly. So, I'd like to know a little bit more about her motivation and why."

Perhaps tonight's appearance of Caitlin's old boss Amunet (Katee Sackhoff) will shed some light on that motivation and why. If the ladies can survive 'Girls Night Out' that is.

'Girls Night Out' will air tonight at 8/7c on The CW.