In my opinion there are a few themes which succeeded in receiving so many literary, artistic and even scientific analysis as Grail. A look at this reality is full of controversy and extremes. Everything depends on the point from which the reality is observed. Full of mystery tales of medieval knights became the reason of the attentive looking at the most important romantic novels of Grail. In these texts, it appears in various forms, hence came the question: What was the Grail? The most common answers are: 1) a container for a stained with blood, severed head; 2) a wide and fairly deep jeweled plate; 3) the dish of the Last Supper; 4) an object made of difficult to define material; 5) a beautifully decorated dish in the shape of the cup; 6) a cup filled with blood of the Savior; 7) a small stone. As a result of an error Grail was also called Sankgreal. So as we see among many answers to this question, there are very extreme opinions. They are represented by the work of two women: Jessie L. Weston from the early twentieth century and Janice Bennett written a few years ago. All these searches lead to two symbols: “the cup (of wine)” and “blood”. The reality, which we try to touch in this study appeared to us in a very complex form, both in terms of texts, which should have been analyzed as well as the source of the theme of Grail. Studies may be very different, and the results difficult to predict. However, the themes of wine and blood present in the descriptions of institution of the Eucharist at the Last Supper, became the guides in the search. It seems that something had to decide on the uniqueness of the dish that has focused an interest of so many literary, artistic and scientific works. In my opinion it was the wine which has been transformed by the Savior into His blood. This reality can be seen as a literary theme shared by many romantic novels of Grail. It could also be seen as the cult of relics of the Savior, as in the history of the Chalice of Valencia Cathedral. Invariably, however, it is still the extremely fascinating subject and let it remain.