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