In Shawshank Redemption, how did Andy Dufresne dig a tunnel if there was a cell next to him. He had to go through it, yet he obviously didn't.
Andy, as both a model prisoner and a cog in the warden's money laundering scheme, was given 2 priveleges; the last cell on the end of the row (a coveted cell for Andy because of its distance from most activity, which made it quieter), and a cell of his own. You may recall that he didn't set out to dig a tunnel, it just started when a chunk of the wall fell out while he was etching on it.
As a result of his 2 privileges, he was able to dig a hole in the wall that led to the sewer pipe, and he was able to do it undetected since he didn't have a cellmate.
If you watch the scene where the warden discovers the tunnel. This is an end cell. The camera goes to the window sill and now from the back of the cell, he throws the conspiracy theory along with the rocks at red and the guards their backs are to the common cell wall. And Fuzzy Brigges is hung on the main retaining wall of the prison.
Although when they first call Dufresne and the cell is shown from the first level from that angle you can't see the poster.