Epic Games has released a realistic Unreal Engine 4 sample along with accompanying documentation to demonstrate the use of high-quality character shader techniques, similar to those used for characters in Paragon, Epic's MOBA for PC and PS4.
The Photorealistic Character sample is available for use in any Unreal Engine 4 project, complete with documentation designed to guide developers through the creation process.
From the announcement:
The purpose of sharing this content is to empower anyone to learn from, explore and deconstruct Epic’s professionally created materials and models. To get started with this showcase, open the Epic Games launcher and download the project from the Learn tab. When you open it, press Play In Editor to see a cinematic pan around the asset.
The documentation released in association with the Photorealistic Character sample, which was created using OTOY facial scanning, delivers insight into the skin, hair and eye shading techniques that provide the ability to achieve photoreal characters in Unreal Engine.