Were you looking for the achievement A Friend In Need?
- "Special 1: Follow the signal to its conclusion".
- "You found the point of contact with Thomas Zane".
After defeating the poltergeist television boss, this achievement will be automatically unlocked, signalling the end of The Signal.
- The name of this achievement "A Friend Indeed" and "A Friend In Need" most likely relates the the catchphrase "A friend in need is a friend indeed".