[Investigation scene, Fathers and Sons] (6)

Head up the stairs to the right inside the church. Turn around at the top and approach the large statue of Mary at the front. Use Mind's Eye to focus on it and dispel the illusion, revealing the 'Cultist Statue' (Key Evidence 1/6) and a new Mind Palace clue: 'It's a cult not a church'.

Be aware of Reed's sanity. Use an antipsychotic or wait for it to restore between sanity-draining events.

Go back downstairs, past the pews, and interact with the file on the table to the right of the piano to find 'Note from the church' [LORE, Documents] (Key Evidence 2/6).

Climb the steps to the chancel and use Mind's Eye to focus on either statue to dispel its illusion, revealing 'Cultist statue' (Evidence 1/5).

Use Mind's Eye on the other statue in the chancel to dispel its illusion, revealing another 'Cultist statue' (Evidence 2/5).

After dispelling the illusion on the alter or both statues, two Lethian Wraiths will spawn. Eliminate them to gain +47 XP each.

Approach the alter and use Mind's Eye to focus on it. This dispels the illusion, revealing 'Dead things in alter' (Evidence 3/5), but will cause a significant sanity hit. A symbol will appear on the back wall of the chancel under the large cross.

Head downstairs to the basement and follow the hallway. Interact with the file on the floor in the middle of the hallway to find 'Dropped note' [LORE, Documents].

Eliminate a small multi-armed wylebeast to gain +20 XP.

Interact with the large pool of ooze after the hallway to find 'Stinky green slime' (Key Evidence 3/6).

Interact with the journal by the corpse in the far corner of the basement to find 'Priest's diary' [LORE, Mythos] (Evidence 4/5).

Interact with the corpse to find 'Chewed corpse' (Evidence 5/5).

Interact with the keyring on the floor by the corpse to find 'A rusty key' [CASEBOOK, Fathers and Sons] (Key Evidence 4/6). Entering the subbasement will remove the casebook entry 'A rusty key'.

Interact with the diving suit at the bottom of the stairs to find 'Diving suit' (Key Evidence 5/6).

Return to the nave on the ground floor and enter the Retrocognition vision.

Find the four critical scenes: on the upper floor in front of the statue, near the top of the stairs to the basement, near the large pool of ooze, and in the middle of the basement.

Mark the scenes in chronological order: 1. on the upper floor in front of the statue, 2. near the top of the stairs to the basement, 3. near the large pool of ooze, 4. in the middle of the basement.

After the vision, you will receive new Mind Palace clues: 'Church records are taken away' and 'The cultists hid under the church', and 'Redemption church cult' [CASEBOOK, Fathers and Sons] (Key Evidence 6/6).

In the Mind Palace, combine the clues 'Church records are taken away' and 'The cultists hid under the church' to deduce 'The answers are underwater' [CASEBOOK, Fathers and Sons].

Head down to the subbasement and interact with the diving suit.