The phrase "on a grand scale" means something that is done or created on a large, impressive and elaborate level. It refers to an event, project or creation that involves a significant amount of resources, time, effort, and attention to detail in order to achieve its desired outcome. The term can be used to describe anything from a lavish party or extravagant production, to a monumental construction project or ambitious artistic endeavor. Essentially, it implies something that is not only large but also impressive, elaborate, and of high quality.