Two scientists are on a secluded island doing experiments on snakes. One of them is Krista Allen (FEAST, FINAL DESTINATION 4) , who is not convincing as a herpitologist at all. In the first five minutes one of them and two local snake wranglers are attacked by a giant mutant reptile. Then, some of the smaller ones get loose. The reason the scientists are doing all this is to create a vaccine, with the snake venom, that will work against most biological war attacks.
Then the military wants to evacuate them because of the threat of the Chinese military and send Luke Perry and his submarine to pick them up. Only the scientists bring the highly poisonous snakes aboard. They escape and start killing the crew. All of them are real snakes except for two really really fake looking computer ones that make ridiculous growling noises. Let's just put it this way-- these snakes are so unconvincing it makes the special effects in an Asylum movie look like AVATAR.
This killer animal movie is better than most of the ones I've seen on the Syfy Channel, primarily because it has a good cast. Also known as SILENT VENOM.