The former Waterloo Road favourite and Strictly Come Dancing star will appear as recurring character Honey Wright in the upcoming series.
Honey is a tea lady with "big hair and a big personality", according to the show, which also teases she'll provide plenty of surprises for the team and is hiding a big secret.
As well as doing the tea round, Honey is experienced at tarot readings and aura interpretations which we predict may cause plenty of fireworks.
Chelsee will start filming her role this week, with her character making her debut appearance in the sixth episode of the new series, airing in October.
"I'm delighted that Chelsee has agreed to bring her unique combination of bounce and style to the Emergency Department," said Casualty's exec producer Oliver Kent.
"Honey Wright is like no other character we've ever featured in Casualty and I can't wait for the audience to see her and her tea trolley in action."
Neither can we! Congrats to Chelsee!
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