the 2014–2015 season. Crystal Ball – Used in the US version of the show, as part of specially designated weeks that used the "shuffle format". When used during the first round, the contestant is allowed to see the cash amount that is designated to the question they are currently on. Plus One – Used in the US version of the show from 2015 to 2019 and since 2020. Based on "Ask One of the Audience", the lifeline allows a contestant to invite on a friend from the audience to come and help them answer the question. There is no time limit, but after that question has been answered the friend has to return to the audience. Ask the Host – Used in the 20th anniversary revival of the original British version; the Danish, French and Italian revivals; Slovenia; Russia (January 2021–present) and the 2020 reboot of the American version. When used by the contestant, the host uses their knowledge of a question's subject, gives their thoughts about the question, and tries to assist them with finding the correct answer out of the choices given. The lifeline features no time limit, and the host reassures all they have no connection to the outside world and receive the question and possible answers for it at the same time as the contestant, and thus have no knowledge of what the correct answer is. After the contestant locks in their answer, the host still can't see what the correct answer is, so they must ask the computer to reveal the correct answer. Top prize winners Out of all contestants who have played the game, relatively few have been able to win the top prize on any international version of the show. The first was John Carpenter, who won the top prize on the American version on 19 November 1999. Carpenter famously did not use a lifeline until the final question, using his "Phone a Friend" to call his father, not for help, but to tell him he was about to become a millionaire. Other notable top-prize winners include Judith Keppel, the first winner of the original British version; Kevin Olmstead from the US version, who won a progressive jackpot of $2.18 million; Martin Flood from the Australian version, who was investigated by producers after suspicions that he had cheated, much like Charles Ingram, but was later cleared; Sushil Kumar from the Indian version, who