It's Bob, the Man on the Moon's birthday - and he's in for a big surprise! Somebody has planned a special day for their favourite Man on the Moon - but who? Bob receives mystery cards and finds presents waiting for him on the moon - but from whom? His friends and family join him for a party in the craters and pose for a portrait; they eat a delicious party lunch and play games; then defy the zero gravity on the bouncy castle - but who could have arranged all of this? Not aliens...surely!