Naked Space 1981
When the spaceship Vertigo stops to explore a previously unknown planet, the crew finds an unrecognized dollop of protoplasm and takes it aboard ship to return it to earth for analysis. On board, lifeform expands into an oozing person-eating monster which communicates primarily by means of a Vegas lounge act. The crew is gobbled up one after another until the two surviving crewmembers come up with a plan.