Sheridan Smith has dyed her hair brown for a part in a show.

Sheridan Smith has dyed her hair for a role in a new show

Sheridan Smith has dyed her hair for a role in a new show

The 42-year-old actress has sported her blonde locks in television shows like 'Two Pints of Lager and a Packet of Crisps' and wore a dark wig when she played the role of comedienne Fanny Brice in a West End revival of 'Funny Girl' in 2016 but has now ditched the colour altogether as she gears up to star in 'Opening Night: The Musical' at the Gielgud Theatre in London.

Speaking in a video posted to Instagram, she said: "So I’m in the hairdressers. This is the last time you are gonna see blonde hair for a long time. I’m about to transform. Ah! Excited!"

The former 'Gavin and Stacey' star - who won an Olivier Award for her starring role as Elle Woods in the musical adaptation of 'Legally Blonde' in 2011 - was seen chatting to hairdressers in the video clip as they got to work completing the lengthy transformation.

Sheridan stars as functioning alcoholic actress Myrtle Gordon in the new musical - which is based on the 1997 drama film starring Gena Rowlands - and will debut in the role when the show premieres on 6 March for a limited run.

The musical's official Instagram account captioned the post: "Watch our GLORIOUS leading lady @sheridansmithster transform into Myrtle for #openingnightmusical."

Several famous faces were quick to comment on the trasformation, with 'Line of Duty' star Vicky McClure posting a heart-eyes emoji and a fire symbol.

Catherine Tyldesley - who is best known for having starred as Eva Price in 'Coronation Street' - also left a string of heart-eyes emojis whilst her former co-star Hayley Tammadon wrote: "Oh this really suits you! Gorgeous!"