Simply, an adventure starts when you have 5 things.
1. A couple good people
2. a couple bad people
3. a problem worth solving
4. some good old motivation on both sides
and finally,
5. Love, and hate, and pain, and friendship and hardship and most of all..
hope. Don't make your story so impossible that there isn't any happiness.
All you need is those five things, and any story you can think of can be, with some effort, brilliant.
for some inspiration, keep this Tolkien quote in mind;
~not all who wander are lost.~