Follow the waypoint to a building near Oscorp Tower to begin the mission. Follow the subsequent waypoint to the glass roof overlooking Oscorp Tower's entrance, which is where Spider-Man can begin tracking the wiring of the building. Press 
to reveal the wiring, and climb up the building to follow it to the first security module straight ahead. Hold 
until Spider-Man finishes the hack, after which you can begin following the next set of wiring. Some snipers will now have their lasers pointed at the building, so make sure to avoid them as you climb (or run) to the right side of the building, where the second security module is located.
The hunt for the third security module is prefaced by the arrival of some drones, equipped with spotlights. These are more difficult to avoid due to the range that they cover, so make sure to mix in some wall-running by holding 
in order to dodge any that get too close. Follow the wiring further right to the third module and hack into it to trigger yet another security measure even more extreme than the last: a helicopter, circling the building and equipped with a massive spotlight. Run left to the fourth and final security module, located inside the "OSCORP" logo on the building. The vent that is unlocked due to Spider-Man's hacking efforts is not far from here. Climb to it and use it to enter the building.
Crawling through the vents will lead you to Norman's office (you can press to find your target, as the vents can be pretty dark depending on your brightness settings). After listening to the discussion below, drop in and approach the computer. Scroll through the slides with 
for some eye-opening information. Spider-Man calls MJ about it afterward, leading into the next mission.
Completing this mission unlocks the College Buddies Side Mission, and completing this Side Mission unlocks another (Tick Tock). Complete Tick Tock for Over His Head, complete Over His Head for A Matter of Debate, and finally, complete A Matter of Debate for Home Team Advantage. All of these Side Missions are located in Greenwich.