Chapter 1-2: ANOTHERLAND
You must get from the initial start of the level to the cut scene with the old woman at the top of the tree in less than 5 minutes.
I noticed that I was pretty close to 5 minutes going as quickly as possible, and without making a mistake, so it doesn't seem like this achievement allows for much room for error; however, if you can do this without making a mistake, then you can simultaneously unlock the
"Can't touch this" achievement.