Alyson Hannigan

A fan of Alyson Hannigan caused chaos at a London theatre after he was found lurking outside her dressing room.

The intruder managed to bypass security at the Haymarket Theatre after a performance of ’When Harry Met Sally’ - in which Alyson stars alongside Luke Perry - and tried to get into her dressing room.

Although the ’Buffy’ star wasn’t there at the time, sources say there was concern about how easily he managed to get so close to her private room.

A source told Britain’s Daily Mirror newspaper: "He was hanging around the stage door after the performance and tried to sneak into Alyson’s room, but was stopped by security. There was a lot of shouting and swearing and staff were concerned about Alyson and Luke’s safety."

A spokesman for the theatre claimed the intruder had tried to get Alyson’s autograph after leaving the theatre through the wrong exit door and finding himself at her dressing room.