Acts

How was the holy spirit working.

As I see it the holy spirit is the same as God and Jesus, so the holy spirit worked and moved the same as God and Jesus. The holy spirit is Gods gift to His followers until He returns. It the way we are connected to God. It's like our WI-FI signal. Being in the right place or close to router, Jesus, our signal is strengthened.

What were the result.

The results of the holy spirit movement was greater then Jesus' work when He was on Earth. I'm not saying it was doing this greater then the sacrifice Jesus made. The holy spirit was able to spread more of the good news and twice the amount of miracles. Also the areas that were reached by the holy
Spirit, Jesus would not have been able to go and preach. Now that Jesus' work was finished, it is the Holy Spirits time to work on earth.

What if the Holy Spirit didn't show up.

I would have to say the world world lost and Jesus would be almost impossible to believe in. If the Holy Spirit didn't come then all of what God had planned long term would have been gone down the drain. Most of all the hope Jesus left with the disciples would have had slowly begin to fade without the Holy spirit.