Thurl Arthur Ravenscroft (/ˈθɜrl ˈreɪvənzkrɒft/; February 6, 1914 – May 22, 2005) was an American voice actor and singer best known as the deep voice behind Tony the Tiger's "They're grrreat!" in Frosted Flakes television commercials for more than five decades. Ravenscroft was also known, however uncredited, as the vocalist for the song "You're a Mean One, Mr. Grinch" from the classic Christmas television special, Dr. Seuss' How the Grinch Stole Christmas!. His voice acting career began in 1940 and lasted until his death in 2005 at age 91.
Ravenscroft left his native Norfolk, Nebraska, for California in 1933. He achieved early success as part of a singing group called The Mellomen. The Mellomen can be heard on many popular recordings of the Big Band Era, including backup for Bing Crosby, Frankie Laine, Spike Jones, Jo Stafford and Rosemary Clooney. Their earliest contribution to a Disney film was for Pinocchio (1940), to which they contributed the song "Honest John." This was deleted from the film but can still be heard in the supplements on the 2009 DVD. They also contributed to other Disney films, such as Alice in Wonderland and Lady and the Tramp. The group appeared on camera in a few episodes of the Disney anthology television series, in one instance recording a canine chorus for Lady and the Tramp, and on another occasion playing a barbershop quartet that reminds Walt Disney of the name of the young newspaper reporter Gallegher.