As Holby prepares for a big charity gala, Guy tasks Arthur with making sure an old patient of his gets the full VIP treatment on Keller, but when Zosia forms a close bond with the gentleman and pushes for a decidedly unconventional approach, Arthur is left scrambling in her wake. Arthur begins to wonder if Zosia is really coping. Jac is determined to make her mark on Darwin and when Mr T brings a special case to her attention, Jac throws herself wholeheartedly into the fray. As the rest of the team get caught up in the excitement of the high-stakes case, Jonny is the only one who questions what's really driving Jac's determination to bury herself in her work. When Billy Tressler arrives on AAU to observe Harry at work, Raf struggles not to let the Tressler family get under his skin.