At over 70 feet in length, you might think it would be difficult to photobomb.

This fin whale proved that size is just a number.

During an early morning briefing along Norway’s northern coast, my guide gave one specific instruction: don't swim over a bait ball. These swirling masses of herring form in defense against orcas, who drive them towards the surface.

The warming stems from the risk of a humpback or fin whale lunging from the depths to feed—advice that's far easier to absorb from the warmth of the boat than in the frigid Arctic waters, where pandemonium plays out.

Chaos arrived on my third morning in the water, when a pod of orcas began their hunt. They circled, pushing the herring into a tighter formation.

My head was on a swivel, trying to capture the orcas in action, when a giant emerged from the darkness below. Focused on the distant shape—and with my mask limiting my peripheral vision—I didn't see the second whale coming straight toward me.

My camera caught it before I did. A flash of gray passed beneath me, and I looked down to find the top of a fin whale—just a few feet under my fins.

I remember blurting a muffled four-letter word into my snorkel and jerking my legs up, as if that would offer any real protection. The truth is, if this whale had wanted to take me for a ride, I wouldn't have had much say in the matter.

Somehow, I managed to keep my camera fixed on the animal, holding the shutter as it surfaced to breathe. An image of the distant animal would have made for a fine memory—but it was the surprise visitor just below that made this one a keeper: the ominous bow of a living cruise ship, forging ahead, stopping for no one.

One of the questions I’m often asked is whether being in the water with these animals is intimidating. Everyone has their own threshold for what feels comfortable—but having a camera in front of me creates a kind of buffer. Not a physical one (a small housing wouldn't offer much protection in a collision with a 50-ton whale), but a mental one. When you're focused on capturing an image, you often become numb to the absurdity unfolding around you. 

There are moments, though, when the absurdity fully registers. 

This was one of those moments.