To get into DarK tube first you must go find it, its located in the subway blocked path next to the Detective office. They will ask for a referal. Then you have to ask the guy at the love clinic about Dark Tube and he will give you a picture. Take the picture and show it to the police man. He will give you the referal. Come back to Gary and he will give you some tools for the mission. this will trigger you calling Chris. Then show up to the Dark Tube Saturday at 1:00 am and get in. The rest is easy to figure out. Good Luck !!!