At the end of World War Two, the Danish Madsen company wanted to replace its production of licensed Suomi submachine guns with a design of its own. The result was the Model 1945, a quite unusual design with a pistol-like slide. The nearest similarities would be the Polish PM-63 and the German VG1-5. The Madsen design also used an unusual hammer firing system. It was chambered for 9mm Parabellum, feeding from Suomi box magazines (not drums). Both a fixed wooden stock version (seen here) and a folding stock version were made, but only a few sales came through (apparently to Mexico and El Salvador).
Danish M1941 Madsen video:
Madsen M1950 video:
“folding stock version were made,”
https://www.firearms.96.lt/pages/Get_Em_Puppy's%20World%20SMGs.html shows said variant in Madsen m/45 and attribute design of fire-arm to Marius Gunnergaard-Poulsen.