Cook strengthened his standup skills by learning the art of improv with Al and the Monkeys, a group he has described as being "like most improv groups, but funny." His solo act eventually became a local favorite and earned enough positive press to attract attention from several late-night television producers. Appearances on David Letterman's and Craig Kilborn's late-night shows followed, and in 2000 Comedy Central invited Cook to helm his own episode of Comedy Central Presents. From here, Cook's résumé filled up quickly with television appearances on The Tonight Show, Crank Yankers, and Suddenly Susan. He also enjoyed small roles in several movies, as well as a cameo in the music video for Smash Mouth's All Star. By the time Cook released his debut album, Harmful If Swallowed, in 2003, he had already become a household name among dedicated comedy fans. The album greatly boosted Cook's profile, however, garnering platinum sales and lofting the comedian to full-fledged celebrity status.
Two years later, Cook's sophomore release, Retaliation, debuted in the Top Ten of the Billboard 200; the double-disc album went gold six days later and reached platinum status within six months, making Cook the highest-charting comedian since Steve Martin. More movies roles followed, including Employee of the Month, Mr. Brooks, and Good Luck Chuck. After releasing two humorous pop singles, neither of which saw much chart success, Cook issued his third comedy album, Rough Around the Edges: Live from Madison Square Garden, in fall 2007. His 2009 effort, ISolated INcident, was recorded in front of a much smaller audience and featured more personal material from the comedian. I Did My Best: Greatest Hits followed in 2010. ~ David Jeffries & Andrew Leahey, Rovi