The actress had to take over Sheridan's lead role of Fanny Brice at London's Savoy Theatre after the 34-year-old star dropped out of a show on Monday (09May16).

Sheridan pulled out of further performances on Tuesday (10May16) and Wednesday (11May16) amid reports she was suffering from exhaustion and from stress due to her father being diagnosed with cancer. The show's producers announced on Thursday (12May16), she would be leaving the production for two to four weeks.

The actress' misfortune left Natasha with the chance of a lifetime to make her debut as the lead in a major West End musical, but she admits she was frightened audiences who had paid for tickets expecting to see Sheridan would react angrily to her.

"Of course I was worried fans would be angry when Sheridan dropped out," the 25-year-old tells Britain's Evening Standard newspaper. "But just because Sheridan isn't performing there is still an entire show to see.

"Most understudies go through an entire run without ever getting on stage. So you're fighting these two feelings knowing it is a dream come true and then facing the reality of taking on this gargantuan, iconic role."

Natasha need not have worried about audiences and critics' reaction, as she has been earned rave reviews for her performance and has been accosted by adoring fans outside the theatre.

Despite her sudden stardom, Natasha is still keen to see Sheridan return to the show, saying, "When Sheridan is away there is a hole in our family, there is definitely something missing and we can't wait to have her back.

"I'm not really sure what's going on in her personal life. She's taking some time out and it's up to us to hold the fort. But we've had to pull together and I'm happy to be here for as long as I'm needed. I'm just doing my crazy job and the show must go on."

Funny Girl, which tells the story of Fanny Brice, a popular film star in the early days of Hollywood, runs until 8 October (16) before transferring to Broadway.

Asked if she would be prepared to continue playing Fanny for the rest of the show's run in the British capital Natasha added, “It would be an incredible opportunity, and I would do whatever it takes to look after myself and put on a great show.”