Giannini passed away on Friday (02Oct15) just hours before he was due to star in theatre production MACk and Mabel in Plymouth, England.

His agent Felix de Wolfe announced the news on Twitter.com, writing, "The talented and much loved actor @GianniniAlex died suddenly of natural causes yesterday. An incredible life force has left the building."

The performance was subsequently cancelled.

Giannini last appeared in recent gangster movie Legend, about the Kray twins. He appeared alongside Tom Hardy as American mobster Antonio Caponigro, also known as Tony Bananas.

He also enjoyed roles in movie Elizabeth: The Golden Age, and TV shows including Transporter: The Series, The Musketeers, The Bill and Dalziel and Pascoe.