1) Their meeting was purely happenstance, as they both happened to be in the same coffee shop at the same time.

2) It was happenstance that the old friends ran into each other while traveling in a foreign country.

3) The success of their business was not due to luck, but rather to happenstance through a series of strategic decisions.

4) The way they found the hidden treasure was pure happenstance, stumbling upon it while exploring the woods.

5) Their paths crossed at the party by pure happenstance, leading to a long-lasting friendship.

6) The discovery of a new species of plant was a result of happenstance, as the scientists stumbled upon it during a routine expedition.

7) The reunion of long-lost siblings was a beautiful example of happenstance bringing them back together.

8) The film's groundbreaking plot twists were not created by happenstance, but rather by careful planning and visionary storytelling.

9) The success of their spontaneous road trip was largely due to the happenstance encounters with kind strangers along the way.

10) The world-changing invention was a result of sheer happenstance, as the scientist stumbled upon the idea while conducting an unrelated experiment.