Demi Lovato is joining Will Ferrell, Pierce Brosnan and Rachel McAdams in the new Netflix comedy film Eurovision.

She will play Katiana, described as "one of the best and most angelic singers in all of Iceland".

The singer and actress' casting coincided with her 27th birthday, and Ferrell announced she was on board with a cake-delivering video message on social media. 

"Hi everyone. Will Ferrell here on the set of my new movie Eurovision," he said. 

"We want to make a very special announcement about a brand new cast member, and it just happens to be her birthday. I made her this wonderful cake from scratch."

Ferrell and McAdams play struggling Icelandic duo Lars Erickssong and Sigrit Ericksdottir with Brosnan playing Lars' father Erick Erickssong, "the most handsome man in Iceland". Downton Abbey's Dan Stevens plays Russian Eurovision contestant Alexander Lemtov.

Ferrell and McAdams are reuniting with Wedding Crashers director David Dobkin for Eurovision. Ferrell co-wrote the comedy, which is currently in production in the UK and Iceland. 

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