Four train-like robots keep transporting iron balls to keep an enormous factory working. The yellow robot loses its strength and is crushed by the iron balls, so the red robot presses a switch and kicks it off. After a while, the blue robot feels exhausted and presses the switch itself to quit. Now, the red robot also ...
一個如城市般龐大的機械工廠裡，輸送帶傳來源源不絕的鐵球。為了讓這座工廠運作正常，四個如火車卡般的小機械人在路軌上不停地運送鐵球。忽然黃色機械人體力不支，被鐵球壓著，紅色機械人便按鈕，把它推離路軌掉了下去。過一陣子，藍色機械人也身心疲累，自己按鈕送自己脫離路軌。現只餘下紅色及綠色繼續不停工作。此時，紅色也……
