The 85-year-old actor is said to be "in good spirits"

Fans reacted with shock and dismay at a performance of the play 'Player's Kings' in London last night after its star, Ian McKellen, fell off the stage.

The 85-year-old actor - who has been appearing in the Shakespearean play, an adaptation of 'Henry IV' parts one and two, since April - is said to have toppled off the stage during a fight scene.

He was hospitalised following the incident, but is thankfully expected to make a full recovery.

The show's producers issued a statement following the accident saying that he will make a "speedy and full recovery" and that McKellen was in "good spirits".

Tonight's performance of the show has been cancelled, they said, "so Ian can rest".

A theatre-goer who witnessed the fall said that McKellen cried out in pain after toppling off stage.

"Sir Ian seemed to trip as he moved downstage to take a more active part in the scene,” an audience member told PA. "He picked up momentum as he moved downstage, which resulted in him falling off the stage directly in front of the audience."

McKellen is perhaps best known for his role as Gandalf in the 'Lord of the Rings' trilogy, which he recently said that he would be willing to reprise for forthcoming film 'The Hunt for Gollum'.