Pollock would often sketch different shapes and forms on paper as a means to expressing his creative side, whilst also potentially trying out new ideas which could then be used elsewhere on canvas at a later date. In some cases his drawings were direct studies, and in other cases purely experimental creations in a similar way to how the Surrealists produced automated drawings, often whilst together in each other's company. The artist here features two clear figures, though they are placed within a complex myriad of lines which make it hard to spot them at first. It is likely that he would have drawn the figures first, and then worked around them to create the final abstraction finish. He used pencil on paper here, certainly nothing unusual in that regard, but he consistently tried any mediums that he could across his career and frequently sought advice from others on other items that he might use. Pencils were accessible and natural to him, and so most of the drawings that we have from his career made use of them either in part or in their entirety.
There is certainly an underlying emotion of fear or terror within this piece and Pollock was someone who had his own inner demons which would cause him great angst throughout most of his life, ultimately leading him to alcoholism. We believe that there are elements here which tell of the influence of Mexican muralist José Clemente Orozco and there is plenty of documentation around that connection from Pollock's career. He would look at many surrealists for inspiration and ideas about connecting with the subconscious but around this time it was the Mexican who was particularly prominent in his thoughts.
The piece remains in the collection of the Museum of Modern Art in New York, USA. They specialise in art from the 20th century and hold an enviable selection of work which has been acquired from a combination of private purchases and generous donations. Some of the highlights to be found here include Les Demoiselles d'Avignon and The Persistence of Memory though there is plenty more to see from a truly impressive lineup which takes in most of the major American and European artists from that century, and continues to cover over global regions more in-depth each year. You might also be interested in René Magritte's The Empire of Light and False Mirror, with this Belgian being regarded as one of the most influential surrealist artists, a movement which itself is known to have greatily influenced the work of Pollock as he continued to develop new ideas across his career.