What are the possible plotlines in 'Scotland Yard meets John' fanfiction?

I'm not sure about specific 'Scotland Yard meets John' fanfiction. But you can try searching on popular fanfiction websites like Archive of Our Own. They usually have a wide range of fan - created stories, and you might be able to find something that fits this theme by using relevant tags.

Maybe a plot where a dangerous international criminal has set their sights on London. Scotland Yard is overwhelmed, and they reluctantly turn to Mycroft for help. Mycroft, in his usual aloof manner, initially seems uninterested but eventually gets drawn into the case. Along the way, there could be a clash of methods between the Yard's traditional investigation techniques and Mycroft's more unorthodox ways, leading to some tense but also humorous moments.

Definitely 'The Nine Tailors' by Dorothy L. Sayers. It showcases a mystery that Scotland Yard detectives would be involved in solving. Also, 'The Woman in White' by Collins is a classic that has elements relevant to Scotland Yard novels. In addition, 'The Big Sleep' by Raymond Chandler, although set in a different context, has detective work similar to what might be associated with Scotland Yard in terms of the investigation and solving of crimes.

One possible plotline could be that the female character gets pregnant while John is away, and when he returns, he has to face this new situation and decide whether to stay or leave. Another could be that they both planned for a baby before John had to leave, and the pregnancy becomes a source of hope and strength for them during their separation.

One possible plotline could be that Naruto is somehow transported to Constantine's world. He has to quickly learn about the magic and the dark forces there. Using his ninja skills and determination, he teams up with Constantine to fight a powerful demon that is threatening both worlds. Another could be that Constantine visits Naruto's world and finds that the chakra system is a form of magic he can tap into. Together, they use this new knowledge to fight off an ancient evil that has been awakened in Naruto's world.

There could also be a plotline where there is some sort of danger threatening the Pride Lands. Kovu and Mufasa, despite their differences, team up to face this threat. Kovu brings his unique skills and knowledge from his pride, and Mufasa uses his wisdom and leadership. As they work together, they develop a mutual respect for each other that was not there before.

Maybe Talion could help Frodo on his journey to destroy the One Ring. He has his own combat skills, so he could offer protection against the various threats that Frodo faces.

One possible plotline could be a competition between Naruto and Sebastian. For example, a contest of skills where Naruto shows off his ninja moves and Sebastian displays his butler feats.

A possible plotline could be that Yugito is kidnapped by an enemy organization. Naruto hears about it and decides to rescue her. Along the way, he discovers more about Yugito's past and the importance of the Two - Tails to the Hidden Cloud. Another plotline might be that they both enter a mysterious ninja tournament. There, they have to fight side by side against powerful opponents and learn to trust each other's skills.

One possible plotline could be that the oc is a powerful enemy who initially challenges Sasuke. But as they face other threats together, they gradually become reluctant allies. Another could be that the oc is a healer who tries to cure Sasuke of some internal injury or curse mark problem. Or perhaps the oc is a time - traveler who has come to change Sasuke's fate, which would lead to a very complex and interesting story.