When the bright star Betelgeuse explodes, it will be an impressive sight. The stellar explosion, known as a supernova, will be brighter than any planet and almost as bright as the full moon. It will be visible during the day, and you could read a book to its light at midnight. It will last a few months before fading away, as all supernovas do.
But it won't be dangerous. For that, it would have to be much, much closer; Betelgeuse is roughly 650 light-years away. So are there any stars that pose a threat to us?
