Hidden Agenda is a mission in Marvel's Spider-Man. Yuriko Watanabe contacts Spider-Man to let him know they located the evidence from the Dual Purpose mission, but that none of it points back to Martin Li. He decides to return to the F.E.A.S.T. shelter to see if he can find any information.
While there as Peter Parker, he suggests to Aunt May that Miles Morales might be a good person to hire. He then decides to search Li's office, but when it is locked, players are forced to use the ventilation ducts as a point of entry. Once inside, Peter discovers a journal with a key in the desk drawer, a picture of Li and May, and a note to May. The picture lets him know where a hidden access point is – namely in the shrine behind the picture. After completing a simple puzzle lock (making a Taoism symbol) a room opens beyond.
There are things to look at throughout the room, but one of the most important is the file folder on the desk. It is the same one Mary Jane Watson found at the auction house earlier. Peter unfortunately trips a booby trap that turns the room into a sparking "burn room".
Players need to hang upside down from the ceiling and use their Electric Web to short out the circuit breakers all over the room to disable the trap. Once accomplished, Peter is free to descend, then access the small room beneath the grating. Finding his way out of this room is a simple task, but he runs right into Martin Li as he does so.
Their very short conversation is interrupted by Aunt May. Li does not seem concerned that he found Peter exiting the room, only announcing to Peter and May that he will be leaving town yet again. Peter follows him outside, watching him get in his car, but then is attacked by homeless people who are apparently under sway of Li's "negative" power. Only when they are knocked unconscious do they return to normal.