John has only a year left to live. The news leaves Sherlock distraught and broken, but Sherlock makes a vow to make the last year of John's life the best year he's ever had. This is Sherlock's last vow.
To see life fade from your loved one, to not feel their pulse, breaks you and you can never fix it however hard you try, it can never be fixed for as long as you live. This is the story of the man who had lost the only person he loved but can that person return before he attempts to join them. John and Sherlock never lived a danger free life, but know everything was crashing all around them, and as John pulled himslef from the rubble to move on from his past Sherlock, the only question is can Sherlock do the same or will he fall further than ever before?