One longjaw (background) preparing to eat a dead or paralyzed longjaw(foreground). Cannibalism isn't really that strange in spiders, it's one of the reasons that we can't harvest spider silk like we harvest caterpillar silk. But there is something weird about this scene.
I'm not an expert, but the spider in the foreground has small pedipalps and what appears to be a large, hardened epigynum. I think this spider is a female. The spider in the background has large palps (which are used to deposit sperm into the body of the female). The background spider is also smaller, especially in the abdomen. This seems to be a male.