Here is the full list of all 42 Hidden Agenda trophies - there are 21 bronze, 18 silver, 2 gold and 1 platinum.
Earn all other trophies
The Trapper is arrested
The Trapper dies
The Trapper tries to commit suicide
Felicity tricks the killer into an ambush
Becky defuses a bomb
Becky's partner helps her escape the cops
The investigation hits a deadend
Finn teams up with Adam
Becky murders her sergeant
Becky shoots Judge Vanstone
Becky catches a prowler in the cabin
Becky tells Finn about Calvary's murder
Vernon LeMay falls to his death
Complete Story Mode
Daniella Cárdenas identifies the Trapper
Finn leads Becky to Adam
Finn escapes from police custody
Becky uncovers Adam's backstory
Felicity convinces Judge Vanstone to release Finn
Unanimously agree on a Trust question
Complete an Endgame Agenda
Complete the game without ever using a weapon
Complete Competitive Mode
Becky and Felicity both die
Felicity burns to death
Becky dies in an explosion
Simon is revealed as the Trapper
Felicity breaks into Simon's residence
Becky is drugged
Becky finds the spycam
Becky links the hooker to two previous murders
Takeover a takeover
Becky finds Father Rominski's "Play Room"
Becky swears at her partner
Find every clue in a single search
Win a Hidden Agenda
Unanimously identify who has the Hidden Agenda
Foil a Hidden Agenda
Don't shoot during a combat event
Succeed on a Quick Time Event
Make your first choice