"You don't have to jump. Just run!"
The guide is trying to reassure me, but it's not the jumping I'm worried about.
It's not the falling, either. The water at the bottom of the falls is quite deep; not deep enough that I won't hit the bottom ("frog legs", the guide warns me), but deep enough to break the fall.
Unless, of course, I slide sideways on the steep slippery rock and smash into the rocky channel carved by the falls.
I'm already desensitised to the five-metre drop: I've jumped worse that morning. It's the runup that's the problem. It doesn't help that one of the group of twenty or so, a young woman, is flat-out refusing to do it. But the canyon has steep sides, so there's no other way down.
I've waited too long; the best move is to go straight away or not at all. I wish, again, that I was wearing my climbing shoes instead of a restrictive wetsuit and reef boots.
Step - step - a second's pause, and a disorganised splash. I recover and breaststroke to the edge. Lyn's starting her run.
Step - she slides sideways. I'm sure she's going headfirst on to rock. But she slams out her right arm, shoving away the rock long enough to fall in cleanly. It happens so fast that she doesn't remember doing it, though her fingers are bruised.
It's the scariest and most dangerous move we make as we work our way back down the canyon. Climbing up it in the first place runs a close second. We both opt out of the twelve-metre jump into a rockpool, preferring to go from six metres, and from the final slide which, according to the guide, is "not really safe". Still, by the time we reach the bottom, we've slid down rocks feetfirst, headfirst, on our backs and on our stomachs, and once even blind. It makes the slides in Langkawi seem insignificant.