I have a friend, let's call her Jenny. Jenny is about six months into her degree and just beginning to discover the true extent of the literature which might be relevant to her topic. By which I mean - she's completely and utterly freaking out. At the start of her journey Jenny read a few things her supervisor suggested and then went off exploring. She did all the right things. Her journey started with a meeting with the subject librarian who taught her how the databases in her area worked and how to use Google Scholar properly (not everything is in there, just so you know). She learned how keywords work and, most importantly in my view, how to do citation searches. Jenny trawled through the databases and discovered a vast amount of stuff which, although it was interesting, seemed only peripherally related to her topic. She read the literature she found, discussed ideas with her supervisors and some of her peers, wrote a bit, then read some more. Her ideas about her thesis changed; becoming more sophisticated and thoughtful. As she read on she started to recognise the same names started appearing in the bibliographies. She started to see how people were linked together in skeins of thought. Being a social type of person she did a bit of academic networking and started to know, socially, some of the people who wrote those papers. This made her feel more confident. Comfortable even. Part of the community. Until she downloaded THAT paper.
Some time ago I wrote a post called "The Valley of Shit", which has become one of the most popular posts ever. Briefly, the Valley of Shit is a state of mind where your thesis seems terrible, awful, bad. Walking though the Valley of Shit is a ghastly business because, well - it smells. But every Valley has an end, as I pointed out in the post, and eventually you will emerge from the towering walls of brown stuff, hopefully with a PhD in your hand.