Rick followed suit and leveled off in the water in diving position, but he hesitated, waiting to see what the boat would do.
It didn't take long to find out. The boat stayed on a perfectly straight course, headed directly for them. Rick waited. Perhaps the shadow intended to sheer off when he got close. He might have come out to talk with them.
Scotty hooted four times, their signal for danger! Then he went under. Still Rick hesitated, until it was clear that the boat did not intend to swerve. He saw the shadow's face, set in grim lines, then his legs went up and he slid under, using his hands as well as his legs to pull himself down to safety. He thought incredulously, "He tried to run us down!"
A dozen feet under he turned over on his back and saw the bright circle of the propeller and its trail of foam. The boat was past. He shot to the surface and filled his lungs with air, waiting for the next move.
The boat spun around in a tight turn and headed back.
Scotty surfaced next to Rick, pulled the snorkel from his mouth, and gritted, "Swim away. Let him use you for a target. I'm going to get that son of a spiny sea walrus."
Rick saw from the position of the spear in Scotty's gun that his friend had charged the weapon during the dive. He nodded, then turned and swam away, flippers flailing as though trying to hurry. He watched over his shoulder and saw the boat head for him.
He was breathing hard from the excitement now, but he took a deep breath and got ready to dive. But still he swam, leading the rapidly overtaking boat until it was almost on him. Only then did he shoot downward, twisting as he went. He looked back in time to see Scotty sight the spear gun and fire as the boat went past.
At first Rick thought his pal had missed, then he realized what Scotty had done. The spear shaft was attached to a long wire leader, and the leader to a safety line coiled around a spool just ahead of the pistol grip. Scotty had deliberately fired ahead of the propeller, knowing that the wire leader would be caught and would wrap around the shaft.
Rick saw the spear stop short as the wire caught, saw it hauled back against the propeller and drop free as the prop blades cut it loose. Scotty shot up for a breath, then dove instantly, toward the rapidly falling spear.