The clock tower gate is the gateway to the Movements which leads to the Belfry Clock, when Luigi first entered he realized that the clock hands and the rotar is missing, then E. Gadd contacted him that the ghost are so smart that they hidden the clock hands and rotar. In C-Boss "Showtime" Luigi repaired all of the gears back to the gate and proceed to the movements. In C-4 "Play catch", JambooLaya can be found here, and a hidden box which contains a gem