Considering the comic book-derived personas and pop culture-obsessed tendencies of underground hip-hop artists MF Doom and Danger Mouse, it should come as no surprise that the two should collaborate on an album featuring cartoon characters from the uber-hip Adult Swim network. THE MOUSE AND THE MASK is an occasionally surreal, frequently humorous, and always mind-expanding jaunt through rap's more intellectual reaches. While Space Ghost and Harvey Birdman Attorney At Law rub shoulders with real-life MCs Talib Kweli and Ghostface, the Danger Doom duo's rhymes dominate the proceedings, wasting no time in skewering the lamentable state of mainstream rap and hip-hop culture. Musically, most tracks are sparse, drawing samples from what sounds like everything from spooky gypsy violin music to greasy 1970's funk to groovy '60's beatnik music. Perhaps the most telling track, however, is "Old School," which celebrates the virtues of making music for the pure enjoyment of the craft.