Tennant will be seen this Christmas in a Doctor Who special
The Royal Shakespeare Company is to reissue some tickets to its production of Hamlet, starring David Tennant, amid fears counterfeits are circulating.
Concerns were raised after forgeries were presented at London's Novello Theatre where the show opens this week.
"Our main priority is that genuine RSC ticket-buyers are protected," said its executive director Vikki Heywood.
"To this end, Delfont Mackintosh Theatres have issued new secure ticket stock," she continued.
"We are confident that this will ensure legitimate RSC audiences get to their rightful seats."
Around 800 people who bought their tickets through Delfont Mackintosh have been asked to arrive early to their designated performance for a ticket exchange.
The vast majority of theatregoers who bought their tickets through the RSC are unaffected.
Ms Heywood said the company was "extremely concerned" the production was being targeted by forgers.
A joint statement from Delfont Mackintosh and the RSC has urged anyone buying tickets through unauthorised outlets or over the internet to be "extremely cautious as to their legitimacy".
"Recently we have seen a growth in auction and ticket re-sale sites on the internet," said Delfont Mackintosh chief executive Richard Johnston.
"None of these companies are authorised agents of our theatres."
Tickets for Hamlet's London run sold out in under three hours when they went on sale in September.
The show runs at the Novello Theatre in London from 3 December to 10 January.
The play, which also stars Patrick Stewart, played to full houses in Stratford-upon-Avon earlier this year.
Scottish actor Tennant will be back as Doctor Who this Christmas in a special entitled The Next Doctor.