O Come, All Ye Thankful

"Cisco Ramon: It's a holiday when we all get together and celebrate and eat a ton of food. Like, a gross amount.
Sherloque Wells: Again, what the difference between this day and every other day in America?"

—Cisco Ramon and Sherloque Wells

"O Come, All Ye Thankful"
Information
Season 5 » Episode 7
Episode number	99 of 184
Original airdate	November 27, 2018
Written by	Jonathan Butler Gabriel Garza
Directed by	Sarah Boyd
Guest stars
Reina Hardesty as Joslyn Jackam/Weather Witch Liam McIntyre as Mark Mardon
Chronology
Preceded by	"The Icicle Cometh"
Followed by	"What's Past is Prologue"

"O Come, All Ye Thankful" is the seventh episode of the fifth season of The Flash, and the ninety-ninth episode overall. It aired on November 27, 2018.

Synopsis

While Nora grapples with unresolved anger over her father’s disappearance in the future, Barry and Team Flash must stop a powerful new meta, Weather Witch, from killing her own father Weather Wizard.

Trivia

• This is the first episode of the series to not feature Hartley Sawyer (Ralph Dibny) and Danielle Nicolet (Cecile Horton) after being promoted to series regulars.
• The episode's title is a play on the Christmas carol "O Come, All Ye Faithful".
• Sherloque refers to Cisco as "young Ralph Macchio", an actor best known for his role as Daniel LaRusso in The Karate Kid franchise.
• Similar to "Therefore I Am", this episode also reveals the origin story of the main antagonist and is the 7th episode of a season.
• When Barry and Iris put Joslyn's staff in the pipeline cell under the control panel in a sign that says 52. This is a reference to the New 52 comics.

Goofs

• When Barry turns around to see the lightning bolt about to hit the generator, his suit briefly switches to the new design and then reverts back when he's running.