The first group on the Periodic table
Be Careful! They're not something to play with!
Alkali metals are very reactive! This makes them very dangerous, as they could easily cause an explosion or injury somebody.
All discovered Alkali metals occur in nature, and they also all react with water.
They also have very similar properties: They're all shiny and soft at standard temperature and pressure, and readily lose their outermost electrons to form cations with charge +1