First it was Mount Agung in Bali. Then it was Mount Sinabung, lying north along the Indonesian coastline.
Now Mount Mayon, the most notorious volcano in the Philippines, has burst into life, with lava spewing down its graceful slopes and threatening the nearby city of Legazpi. A Philippine Institute of Volcanology and Seismology official said at the weekend that the volcano's swollen sides suggest that it could erupt explosively.
The local government has declared a state of calamity, and more than 80,000 people have already fled the area. An 8-kilometre exclusion zone has been established, and the volcano put under the same intense scrutiny as its two simmering siblings.
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While those living in the shadow of these towering infernos anxiously watch and wait, it is hard to avoid thinking these events are no coincidence.
The resurgence of three volcanoes in the same region of the world seems to demand the existence of a hidden connection — one that might even drive a global apocalypse.
Such nightmarish thoughts are not so far from the reality.
There is indeed a connection between the three volcanoes. They are all part of the so-called Ring of Fire, a colossal arc of shattered crust wrapped around the edges of the Pacific Ocean.
Extending more than 40,000km from New Zealand, curling round the coast of Indonesia up to Alaska and back down to Chile, it marks the boundary of a set of tectonic plates that make up the outer shell of the Earth.
Propelled by the heat from the radioactive rock beneath them, these plates are in constant motion, slipping and straining against each other.
Some slide against each other, tearing rock apart and triggering earthquakes. But in the Ring of Fire they go head to head, trying to force each other down into the depths of the Earth.
And when they succeed, the vanquished plate melts the surrounding rock, which wells upward to form whole chains of volcanoes.
Mount Agung and Mount Sinabung are the visible signs of a primordial tussle between the Sunda Plate and the Indo-Australian Plate, which was driven down into the Earth’s mantle.
Mount Mayon was formed 20 million years ago during the clash of the Philippine Plate with its Eurasian counterpart.
But these struggles never cease. Every so often, conditions beneath a volcano change, sometimes making it burst back to life with devastating effect.
When Mount Agung last erupted in 1963, it killed almost 2,000 inhabitants of Bali. Mount Sinabung erupted after centuries of dormancy in 2010, and has been simmering ever since.
Mount Mayon has erupted at least 50 times over the last 400 years, most recently in 2014. Its most violent outburst was over a century ago, when around 1,200 people lost their lives.
So what should we make of all three of these volcanoes coming back to life within weeks of each other?
The Ring of Fire provides the connection — one that has led to the creation of over 400 active volcanoes, with over 100 in Indonesia alone.
But by the same token, there is no need to view the simultaneous outbursts as some kind of portent of impending doom.
The law of probability shows that, given so many volcanoes in the region, it is far from unusual for three to rumble into life at the same time.
But that same law suggests that one day we may witness the simultaneous eruption of a whole host of volcanoes, with catastrophic global consequences.
In the long history of the Earth it has happened many times, leading to mass extinctions.
Chances are it will not happen any time soon. But when it does, make no mistake: it will be a catastrophe that engulfs us all.
Robert Matthews is Visiting Professor of Science at Aston University, Birmingham, UK
