This article covers a subject that is part of the real world, and thus should not be taken as a part of the Holby universe.
"Mistletoe and Rum" is the first special episode in the 27th series of Casualty. It was directed by Sunetra Sarker, the actress who portrays Zoe Hanna, and written by David P. Davis. It aired directly after the episode "I Saw Mommy Killing Santa Claus".
It's Christmas Eve and the nurses from Holby ED head out to party. Fletch dreads all the stress that the big day brings, so he busies himself sorting out everybody else's problems.