Dear detective tapes

The Dear detective tapes are a series of four holotapes in Fallout 4.

Locations
They are left in the Fens street sewer by a Fens Phantom, a serial killer, to portray his kills to a detective on his trail.
 * Tape 1 can be seen right when coming down the ladder from the street.
 * Tape 2 can be found on a barbecue next to a skull.
 * Tape 3 can be found on a table next to a yellow chair in a room with a mannequin, unlit candles on shelves, and various crates.
 * Tape 4 can be found near the end, in an alcove with a safe behind a chain fence.

Related quest

 * Dear Detective