Overkill, the CLEOPATRA of the funnybone. This comic extravaganza starts off funny, but exhausts rather than delights. Designed to be the biggest, most lavish comedy ever made, IT'S A MAD, MAD, MAD, MAD WORLD is a coarse, star-studded pageant of Keystone Kops-style slapstick. With his dying breath, a gangster (Jimmy Durante) recently released from prison tells the motorists who come upon him after an auto accident that $350,000 is buried under "the Big W," instigating a greedy, madcap dash for the cash. Among the lunatic treasure seekers who will stop at nothing to get to the loot first are Milton Berle, Dorothy Provine, Ethel Merman (who, curiously, steals the film from under everyone else's talented nose), Sid Caesar, Edie Adams, Buddy Hackett, Mickey Rooney, and Jonathan Winters. Phil Silvers, Terry-Thomas, Peter Falk, Dick Shawn, and Spencer Tracy also become involved, and the film is a who's who of Hollywood comedians in cameo appearances. Director-producer Kramer spared no expense (tame today, the $7 million price tag was a hefty one at the time) on the spectacular stunts, using 39 stunt men and paying them $252,000 for some of the most incredible feats on film. But at 154 minutes of running time, it's way too long for what it is. Watching it at home with breaks may be the best way to analyze individual comic takes; certainly it's the most painless.