David Lynch's movies are not easy to review, in fact I think words can not describe Surrealist "movies" generally speaking. Yeah I put that by purpose in brackets because they are not like ordinary movies where you expect a clear storyline, character development, an appropriate soundtrack and so on, but here you really have to feel them and be in the correct mood, have enough concentration and be open minded and patient.
You can ask ten people what _Eraserhead_ is about and you'll get ten different answers, so there is no really 'get it' or right or wrong rather a lot room for interpretation and conjecture.

Anyway _Eraserhead_ is David Lynch's first feature-length film after a row of short movies which are exactly what you think they are, really Lynch-like. We find ourselfs trapped in a black and white, dystopian world at an unkown time and follow the Story of Henry Spencer (Jack Nance) who impregnates his girlfriend and she gives birth to a malformed baby. overchallenged and desperate by that situation she leaves Henry with the baby alone.

That's basically the main storyline and everything that is obvious and clear, adding more to that would be kind of a spoiler and is open to everyone's imagination anyhow.