The cast of ABBA musical adaptation Mamma Mia! is getting more and more crowded. With Meryl Streep, Pierce Brosnan and Amanda Seyfried already in place as three of the leads, Colin Firth, Stellan Skarsgard and Christine Baranski are now joining them.

The plot finds Seyfried about to get married, and confronting her mother (Streep) about who her real father is. She ends up luring three possible fathers – Brosnan, Firth and Skarsgard – to the Greek island where she and her mother live to find out who’s the daddy. Oh, and that procedure involves 22 Abba songs.

Unsurprisingly, Baranski won’t be playing a dad candidate – she’s playing a friend of Streep’s known for her wild behaviour.

Phyllida Lloyd, who has directed the musical on the stage, will step up behind the camera for a shoot stretching from June until October in London and Greece.