All you have to do is go to were you met the strange man and enter the tunnels there
In the bin near the tunnel entrance.
You return them to the guy in the internet cafe.
You cannot enter the museum until you have taken the Underground Tunnel Tour.
Before you can enter the museum, you have to take the Underground Tunnel tour.
You can look around the island all you want. The "Underground Tunnel Tour" requires tickets. (see related question)
Most are just distractions (for the "blue hand"). But you can dig through one of the pair of large trashcans to the right of the Underground Tunnel Tour entrance.
Halfway through the Underground Tunnel is a high arched dome in the ceiling. Climb up the light bulb cord to the very top, and jump right to grab the piece.
it means that you have to go up the broken ladder in the underground tunnel
To get the museum to let you in on Counterfeit Island, you have to go through the Underground Tunnel, then exit the tunnel, where it leads you to the City Docks. There will be a man waiting near the exit and he'll tell you to get a job at the museum, then meet him at night. You go to the museum and tell the guard you're there to apply for the job. He'll let you in the museum.
on top of buildings and by windows and stuff they help u where the underground tunnel tour.
You have to find all the pieces of the picture, so that you can open the secret entrance in the underground tunnel.
At the museum, you can't enter until you have taken the Underground Tunnel Tour. (see related question)