Slater's co-stars include Frances Barber and Mackenzie Crook

The US actor took part in the public dress rehearsal of One Flew Over the Cuckoo's Nest at the Assembly Rooms in Edinburgh, as part of the Fringe.

Speaking after the show, the True Romance star thanked the audience for being "fantastically supportive".

The play's first night was delayed for four nights after Slater, 34, became ill during rehearsals.

The play, adapted from the book by Ken Kesey, has been beset with problems, including director Guy Masterson quitting weeks before the scheduled opening night.

Mr Masterson blamed stress for his decision to leave the production. He was replaced by co-directors Tamara Harvey and playwright Terry Johnson.

Relapse

Slater then came down with chickenpox after catching it from a fellow cast member.

It initially appeared as if only the first night would be postponed, but Slater developed a secondary infection and exhaustion and the next three performances were also called off.

A show spokesman said of Slater: "He's got so much energy for the show and he's hopefully going to continue the run as it is from now until the end of the month."