The original series aired for 30 series and aired a total of 592 episodes, from 4 September 1998 to 11 February 2014, and was presented by Chris Tarrant. Over the course of its initial run, the show had five contestants achieve the ultimate aim and walk away with the cash prize of £1 million. The original format of the programme was tweaked in later years; this included changing the number of questions from fifteen to twelve, altering the payout structure, incorporating a time limit, and adding an attainable fourth lifeline. There were several controversies during its run, including an attempt by a contestant to defraud the show of its top prize.