I’m assuming this issue was intended to cross promote Ka-Zar’s new series–which incidentally is one of the best new series of this era.
Peter Parker is sent to the Savage Land to take pictures of how climate change is affecting the region. SHIELD accompanies him. While he’s there, it’s a Ka-Zar/Hulk/Spidey team up to uncover a Roxxon Corporation conspiracy to take over the Savage Land.