A Long Night

A Long Night is a single-player downloadable content addition for Assassin's Creed: Syndicate and will be released with the game as part of the game's Season Pass.

Official synopsis
Help Jacob track down an endangered fellow gang member and bring him back to the hideout in a fast-paced, wild and dangerous ride.

Reference

 * Ubisoft - Assassin's Creed: Syndicate Season Pass