While traditional live-broadcasting is typically comprised of a handful of well-defined workflows, these become insufficient when targeting multiple screens and interactive companion devices on the viewer side. In this case study, we describe the development of an end-to-end system enabling immersive and interactive experiences using an object-based broadcasting approach. We detail the deployment of this system during the live broadcast of the FA Cup Final at Wembley Stadium in London in May 2018. We also describe the trials and interviews we ran in the run-up to this event, the infrastructure we used, the final software developed for controlling and rendering on-screen graphics and the system for generating and configuring the live broadcast-objects. In this process, we learned about the workflows inside an OB truck during live productions through an ethnographic study and the challenges involved in running an object-based broadcast over the Internet, which we discuss alongside other gained insights.