Louis (Rick Moranis)’s Timeline and Summary

Louis awkwardly invites Dana to his party.
He's disappointed when Dana makes a date with Venkman.
His party is disrupted by the terror dog Vinz Clortho.
Vinz Clortho chases him through Central Park and finally catches him at Tavern on the Green.
Now possessed, Louis/Vinz runs crazily around the city.
Louis/Vinz is brought by a cop to the Ghostbusters.
He escapes after the big explosion and unites with Dana/Zuul.
With Dana/Zuul, he ushers in the coming of Gozer.
Louis is rescued from the ashes of Vinz Clortho by the Ghostbusters.
He's taken away by paramedics.