When Lindsay Lohan was cast in David Mamet's Speed-the-Plow back in June, she claimed to be "nervous but excited" about her theatre debut. Unfortunately, in the first previews of the show in London's West End on Wednesday (24th September), nerves reportedly got the better of the Mean Girls actress.

Lindsay Lohan
Lindsay Lohan at the 2014 GQ Awards.

Read More: Lindsay Lohan, Determined To Prove Critics Wrong, Promises Not To Miss Any West End Shows.

Lohan is playing Karen, a secretary for two Hollywood producers who is placed in compromising positions by her employers when they both attempt to seduce her. Although Lohan is not the lead and only has one key speech she apparently forgot a number of her lines. 

According to reports in USA Today and MTV, Lohan was reliant on a book she was using as a prop in which she'd written a number of her lines. Yet that wasn't all, apparently those working back stage kept shouting Lohan's lines to her yet she still managed to forget a large portion of Karen's one pivotal speech. 

Read More: Lindsay Lohan and James Franco - Did They Or Didn't They?

Lindsay Lohan
Lindsay Lohan enjoying a night out in London in June.

For the sake of fairness, it should be noted this is Lohan's first stage performance and she's certainly had a number of personal problems over the past few years. However, the Independent claims the role of Karen is ideal for someone unused to the theatre. Their reporter, Emily Jupp, wrote "It's ideal for a first-timer because although the part of Karen is critical to the story it isn't a huge role and she doesn't even appear on stage for most of Act One."

Fortunately for Lohan, Speed-the-Plow is only in the early stages of its West End run and she still has time to improve. However, audiences seeing the early performances should be duly warned of Lohan's nerves. 

Lohan stars alongside Nigel Lindsay and Richard Schiff in Speed-the-Plow at the Playhouse Theatre. The show runs until 29th November.

Read More: Lindsay Lohan To Write Three Part Memoir.

Lindsay Lohan
Lohan in Soho, London in August.