The invention provides a door device (1) adapted to provide a watertight condition against an external surface, the door device (1) comprising a main support surface (2), a main spar (10), first and second main closing elements (3, 4), first, second, third and fourth connecting elements (5, 6, 7, 8), primary guiding elements (91, 92), a transversal element (11) comprising an auxiliary closing wedge (111) and secondary guiding elements (93, 94), wherein along the movement of the main spar (10) between a first inactive position and a second watertight position, the movement of each second connecting element (6) is limited by the corresponding primary guiding element (91, 92) to the direction of said primary guiding element (91, 92), making the first and second main closing elements (3, 4) exit a main area (2a). When the main spar (10) is in the watertight position, the watertight gap is equal to the length of the watertight side of the auxiliary closing wedge (111). The invention also provides a watertight system and a method.