Question: Sean Masterson was an improvisational performer on which Drew Carey's show?

Context paragraphs:
Drew Cam: "Drew Cam" is the ninth episode of the fifth season of the American sitcom "The Drew Carey Show", and the 110th overall.  The episode sees Drew (Drew Carey) becoming a 24-hour salesman for the Winfred-Louder department store.  Webcams are installed in his house and he has to promote the store's range of appliances.  While Drew is out, the webcams continue to stream events that occur in his house.  When the viewers become bored of Drew's life, his friend Kate O'Brien (Christa Miller) is hired to play his girlfriend for the show.  Isabel (Rosa Blasi) replaces Kate, who becomes jealous.  She eventually tells Drew she loves him during the webcast.

The Dog and Pony Show: "The Dog and Pony Show" is the eighth episode of the third season of the American sitcom "The Drew Carey Show", and the 54th overall.  The series focuses on the work and home life of a fictionalized version of actor and comedian Drew Carey.  The episode first aired on November 12, 1997 on ABC in the United States.  The episode's plot sees Mr. Wick (Craig Ferguson) pass off caring for his boss Mrs. Lauder's (Nan Martin) Hungarian Puli to his employee Drew (Drew Carey).  When Drew has the prize-winning dog shaved and neutered, he and his friends decide to perform a striptease at the local bar, The Warsaw Tavern, to earn quick cash to buy a replacement.

Sounds Dangerous!: Sounds Dangerous!  was an audio show at Echo Lake inside Disney's Hollywood Studios starring comedian Drew Carey.  The presentation took place inside an ABC soundstage with theater-style seating.  Guests were told that the show is an ABC test pilot called Undercover Live.  Guests wore headphones and were in the dark for the majority of the show, however visuals were also utilized on a projection screen in front of the guests.  Drew Carey played an undercover detective named Foster.  In early 2009, it was announced that this attraction would operate seasonally.  The image of Drew Carey along with the attraction's name was removed from the entrance's marquee and the screen was turned off, indicating the closure of the attraction, which meant that Disney closed the attraction on May 18, 2012, renaming it as ABC Sound Studio, and redressing it as the temporary "Carbon Freeze Me" attraction for the park's annual "Star Wars" Weekends event.

List of The Drew Carey Show episodes: The following is a complete list of episodes for the television show sitcom "The Drew Carey Show", which first aired on ABC on September 13, 1995.  Throughout the show's run, nine seasons were filmed amassing 233 episodes, with the final episode airing on September 8, 2004.  The sitcom follows assistant personnel director Drew Carey, in his romances and relationships to friends Lewis, Oswald, and Kate.  There have been two DVD releases for "The Drew Carey Show": the first was a six-episode compilation released on February 28, 2006 and the first season was released on April 24, 2007.

Drew Carey's Green Screen Show: Drew Carey's Green Screen Show is an improvisational comedy television series that aired in the fall of 2004 on The WB, and the fall of 2005 on Comedy Central.  The show was hosted by Drew Carey, and was somewhat a follow-up to the show he formerly hosted, "Whose Line Is It Anyway? ".  The distinguishing feature of the show was that the improv games were performed in front of a "green screen" (similar to "Newsflash" game from "Whose Line?") , with animation, music and sound effects inserted in post-production.  The show was otherwise very similar to "Whose Line?"  and featured many of the same performers and games.

Sean Masterson: Sean Masterson is a comedy actor, writer, director and producer known for his work with Drew Carey, writing on "The Drew Carey Show", and as an improvisational performer on "Whose Line Is It Anyway?"  spin-offs "Drew Carey's Green Screen Show", and "Drew Carey's Improv-A-Ganza".

Ryan Stiles: Ryan Lee Stiles (born April 22, 1959) is a Canadian-American actor, comedian, producer and director whose work is often associated with improvisational comedy.  He is best known for his career and co-production work on the American and British versions of "Whose Line Is It Anyway?"  and the role of Lewis Kiniski on "The Drew Carey Show".  He played Herb Melnick on the CBS comedy "Two and a Half Men" and was a performer on the show "Drew Carey's Improv-A-Ganza".

Pilot (The Drew Carey Show): "Pilot" is the first episode and the series premiere of the American sitcom "The Drew Carey Show".  It first aired on September 13, 1995 on the ABC network in the United States.  The premise of the show revolves around the life Drew Carey would have lived if he had not become a stand-up comedian.  The pilot introduces the main characters of Drew (Carey), Kate (Christa Miller), Lewis (Ryan Stiles) and Oswald (Diedrich Bader), as well as Drew's workplace, the fictional Winfred-Lauder department store, and enemy Mimi Bobeck (Kathy Kinney).

Cleveland Rocks! Music from The Drew Carey Show: Cleveland Rocks!  Music from The Drew Carey Show is a soundtrack for the ABC television series "The Drew Carey Show", released on May 19, 1998, by Rhino Records.  The album has 24 tracks of songs that have appeared in the show and performances by the cast.  An original composition titled "Bite Me, Doughboy!"  was created for the album by the show's music composer W. G. Snuffy Walden.  "Cleveland Rocks!  Music from The Drew Carey Show" received mostly positive reviews from music critics, who thought the album was perfect for fans of the show.  The album won Best New Material Record Release at the 12th TV Theme Music Awards.

Drew Carey's Improv-A-Ganza: Drew Carey's Improv-A-Ganza is an improvisational comedy television program that aired in the United States on the Game Show Network.  The program was hosted by Drew Carey and was produced at the Hollywood Theatre at the MGM Grand in Paradise, Nevada.  The show premiered on April 11, 2011 at 8 p.m. EST.

Supporting paragraphs: Sean Masterson Drew Carey's Improv-A-Ganza
Answer: "Drew Carey's Improv-A-Ganza"