Encouraging employees to have fun at work improves staff morale and productivity; happy workers are said to be productive workers. However, dissenting voices argue that fun distracts employees from increased demands to work longer hours and increased levels of covert control. Fun has become little more than an opiate for the worker. In this Classical Grounded Theory (CGT), I will contribute to those dissenting voices, not by rejecting the need for employees to have fun but, by exploring the different dimensions of fun; rethinking the concept of fun itself. Much of the discussion surrounding fun at work is positive, focusing on pleasure and entertainment; however, fun as resistance has received less attention. This analysis of 21 unstructured interviews with UK-based employees explored the relationship between fun and workplace behaviour; uncovering the transformative process of Automatonising. The analysis revealed how employees weaponise fun in an ongoing duel for personal power and control with employers and colleagues. Having-Fun, with its focus on shallow fun (instant gratification and harmful competition), harms organisations. In contrast, the process of Being-Fun, which emphasises deep fun (learning, wonderment, and serendipity) offers a means of escaping the duel by focusing on personal, emotional, intellectual and professional growth. A symbiotic study to understand how to use the CGT method, an analysis of 22 primary CGT texts supported the theory of Being-Fun. CGT itself emerged as a subversive research method that promotes the personal and professional development of researchers over the proletarianisation and Automatonising process. The method privileges serendipity and fun, providing a template to use in developing an orientation towards Being-Fun at work, and in broader social contexts. By uncovering the distinct processes of Having-Fun and Being-Fun, this study clarifies, elaborates and extends our understanding of how fun can encourage productive behaviours in our workplaces.