The basic plot: Dangerously-stacked and impossibly-waisted “archaeologist” searches for Mjolnir, Thor’s magical hammer.
Jumps the shark when: Let’s call this one a “double-jump.” First, Lara is accused of trying to kill her own friends, and only later is it clear that some kind of “evil” Lara was responsible - an evil twin with purple hair and yellow eyes. Okay, fine, we’ll roll with that… for a while. Until ZERO explanation is given for the twin’s existence, and then she disappears from the story entirely. Unless you want pay for a vague DLC rationalization, that is.
Above: If you’re gonna raid tombs, expect some (mama) zombies
If that wasn’t horrible enough, Lara later discovers her mother is a zombie. Again, no explanation, but there’s her undead mother, lurching forward to eat her brains. And then POW, Lara puts down her own mother like a broke-legged horse.