“Shampoo time!” grins Eduardo, the podgy Colombian man as he pushes my head back and slaps a dollop of cool, thick, grey gloop on top of my head.
As it dribbles down my forehead someone else grabs my outstretched legs and, pushing me backwards, I glide over the dense pool of liquid for a couple of metres without sinking.
My fits of giggles are only intensified when Eduardo turns masseur and starts squidging the sloppy mass into my arms, neck and belly.
The dozen or so fellow bathers wade around me as they admire the views atop Volcan El Tutumo, a mud volcano around an hour away from Cartagena.
I squeak as Eduardo rolls me over onto my front as if he were turning a piece of toast, and starts on my legs and feet.
His pal Diego, who has just received a gliding Phil into his arms, is keeping a suitably macho face while delicately squeezing his palms and fingers.
I say “volcano” – the age-old mound actually only rises about 50 feet above ground. But the squelchy stuff held in its cavity goes down for a few thousand more, regularly belching up giant gas bubbles from its depths that inevitably spark a round of cheers and an obligatory fart joke aimed at whoever’s nearest.
Once they have done groping us, Phil and I are gently pushed off by our masseurs into the throng of slick, muddy bodies.
“Stand up! Stand up!” shouts Eduardo as my efforts to “tread mud” result in the dense mass slowly pushing me upwards and backwards again.
Our feet floating freely, we experience the bizarre sensation of being dunked under by another guy, who carefully wipes our eyes, mouth and ears clean after we boing back up.
Then it’s more groping, at the hands of a fourth assistant who enthusiastically wipes the excess mud off and out of every crevice before sending us back down the slippery steps to get cleaned.
We can barely move our face muscles as the mud has dried to a caked-on layer. In fact it’s exactly like my usual £5.49 Boots face mask. Only a bit more fun.
Down the hill a large lake awaits, where our fellow bog buddies are already getting bathed, stripped and scrubbed by a gaggle of chattering village women with cloth wrapped around their heads, wet flannels strung over their shoulders and plastic bowls in their hands.
My attempts to plead that por favor, I can wash myself, fall upon deaf ears and the ladies launch into tipping water over my head and cleaning out my ears as if I were a pesky Dickensian street urchin.
I turn to say something to Phil, but see he is being forced underwater by an ample-bodied señora who has simultaneously whipped his trunks off and is busy pummelling them clean(ish).
The mud’s many minerals must have worked a treat, as my skin does feel very smooth.
You can keep your fluffy white bathrobe and slippers. From now on, if it doesn’t come with a sulphurous spluttering volcano, I’m just not interested.