These two episodes come midway through the third season of the show and have the doctors jumping into action following a catastrophic ferry crash. While the first episode mostly focuses on the doctors treating patients who were previously unknown to them, the second hits much closer to home after Meredith is knocked into the freezing water and nearly drowns.
Although none of the main cast members are on the ferry when it crashes, this incident winds up having lasting repercussions for both Meredith and Alex, as Alex eventually becomes romantically involved with the Jane Doe he rescues, and Meredith continues to process what she experienced while she was unconscious for years to come, bringing it up again as recently as the penultimate episode of season 15.