Here is the full list of all 46 Detective From The Crypt achievements.
Find all the pearls
Open the governess version
Open Lady Darkday version
Open version with Aunt Esther
Return the necklace to its owner
Find the use of soap bubbles
Unlock all versions of events
Open all safes
Make Aunt Drink
Open the version with Lord Darkday
Help Mrs Brown
Help a kind mummy
Help the cat mummy
Get sleeping pills from the doctor
Open the Butler version
Help Mrs. Jones
Learn the secret of the automaton
Find a use of the figurine
Find Opals
Listen the audio record
Put the poison into hot chocolate
Find out whose button it is
Test Substances for Poison
Scare the butler to death
Find grandfather's diary
Discover the secret of the library
Find the pocket mirror
Get the second letter
Find the poacher
Find the use of the dung-beetle
Find the rat
Find Anubis Mask
Open the Sarcophagus
Find Pulcheria
Find the diary
Take a blood test
Help the loser
Help the bagpiper
Get a letter from your great-grandmother
Find a pocket watch
Help the Maid
Meet the Greedy Bride
Find family jewels
Find the shackles
Apply magnifier to boots
Apply the magnifying glass on the monument