Refuse them

You back away from the shore. Something about the situation feels... off, and you suddenly realize why: they have no legs. Or, pelvis or feet or anything. You should be able to see any of their lower half in the crystal-clear lake but their bodies simply stop at the water line, as though they're not submerged in the water, but rather emerging from it.

The man you were speaking with sees your obvious refusal, and becomes more forceful.

"What are you doing? Get back here." his smile is gone, "Get the fuck back here!"

He surges towards you and on instinct you leap further back into safety. His grab misses and you watch in shock when before your eyes he crashes into the shore as nothing but a harmless wave, quickly ebbing back into the lake.

He rises out of the water near the other two once more, sending dagger-looks of malice your way.

So much for this being easy.

You decide it's time to stop messing around. The sooner you get across the lake the sooner you can get far away from those... things.