A twin-wire papermaking machine contains a headbox for forming a first fiber ply which is essentially downwardly dewatered at a section of a first wire. At the end of this wire section, forwardly or upstream of the inbound or on-running location of a second wire there is arranged a second headbox for forming a second fiber ply which is essentially upwardly dewatered along a subsequently arranged common path of both wires. The common path advantageously extends over an essentially water impervious, convex domed contact surface of a slide shoe and/or a jacket surface of a guide cylinder or roll. During operation, the second fiber ply is deposited upon the already extensively dewatered first fiber ply and upon passage through the common path of both wires this second fiber ply is dewatered upwardly away from the first fiber ply. This enables separate dewatering of both fiber plies, and there is particularly avoided deflocculation of individual fibers, and thus, impairment of the fiber formation in the initially formed ply.