Guinevere and Lancelot journey to the vault of the Dark One and make their way in. In the vault, Lancelot is almost taken by a vortex, but Guinevere fights against it. Lancelot is released from the vortex and the two share a kiss. When they break apart, Guinevere reminds him that they're there for their king: Arthur. From Once Upon a Time season 5 episode 4, "The Broken Kingdom."