When Gene Kelly teams with Arthur Freed, Stanley Donen, Betty Comden and Adolph Green, the result is pure movie-musical alchemy: On the Town, Singin in the Rain and Its Always Fair Weather. Sparkling with wit and exuberant numbers, Its Always Fair Weather centers on three World War II buddies (Kelly, Dan Dailey and Michael Kidd) who vow to reunite for old times sake in 10 years. They do. And find their friendship has fizzled until a day of tangling with romance, the fight game, the ad biz and a new medium called TV restores their bond. Highlights include the buddies high-spirited romp that uses trash-can lids as dancing shoes, elegant Cyd Charisses k.o. of a routine with brokennosed pugilists, and Kellys joyful, astonishing tap dance on roller skates. Wow!