I had the chance to work as a Consultant Technical Artist at Epic Games in the start of 2019. I have created all the aspects of the scene, with the collaboration of Fabrice Bourrelly.
The purpose was to showcase the new feature of 4.22 release: the realtime raytracing. It allows you to get proper reflections/shadows/translucency/global illumination and also to avoid lightmaps baking (and hours of compiling).
Images are extracted from the UE4 documentation concerning the Ray Tracing features. The scene was also used to illustrate the technology on the GDC 2019.