The phrase you are referring to is "strange bedfellows." It means two people or groups who are normally opposed to each other forming an alliance, usually for a common goal. This expression first appeared in Shakespeare's play "The Tempest," where Trinculo and Caliban hide under a cloak during a storm, despite disliking each other. The phrase has since been used in various contexts to describe unusual alliances, such as political, social, or business partnerships between unlikely partners.
~~~Harsha~~~