Fear is one of mankinds strongest and most primal emotions. There is little anyone can do to control when they will be afraid or what will cause the fear.

Some, however, enjoy being afraid and are willing to pay for the experience.

For the past 13 years, Busch Gardens has been scaring and delighting guests with its annual production of Howl-O-Scream. What began in 1999 as a family themed event called Spooky Safari soon grew into the fully developed adult production of Howl-O-Scream.

This years Howl-O-Scream theme is The Dark Side of the Gardens, which creative director Scott Swenson described as one of the most unique in the 13 years of the events history.

Swenson said this years theme plays heavily off its 13-year history, featuring a Circus of Superstition house that immerses guests in 13 superstitions.

The Dark Side of the Gardens can hold just about anything, and I think that really opens it up to peoples imaginations,

Swenson said. Thats what were here to do to spark peoples imaginations into the nightmarish side, and people can create their own fears inside of that.

Howl-O-Screams themes in past years have exploited common childhood fears such as clowns, and have also created unique fears, such as 2007s Death Jockey, a character who killed clubgoers with his music and lighting effects.

Not everyone is afraid of the same thing, Swenson said. Variety is really our key to success. … One of my favorite moments happened early on. One of our guests was distracted by a street performer, and another performer came up behind him and scared him so bad that he literally leapt out of his pants.

He was wearing those loose pants to begin with, and when he jumped up the pants went down, and it became even more embarrassing, he said. Its just really funny to see the entire cast try not to crack up when something like that happens. The performers look at it as kind of a badge of honor if they can get that kind of reaction out of people.

Swenson said other incidents werent as funny.

Though performers must abide by a no touching rule, Swenson said some performers act as victim guests, blurring lines.

We had a situation in one of the houses where one of the victims came out and began speaking to a guest while waiting in line, he said. The victim told the guest, Im so sorry, but Ive lost my group, can I walk through with you? and made that emotional connection with the guest. And then the guest replied with Ive lost my party too, and Im really scared!

Swenson said he knew then that the situation would turn out to be either really funny or really sad.

So they go through the house together, and the performer gets snatched, he said. The guest turned to me in a panic and saw that I was wearing a nametag. Well, I was feeling a little playful that day, so I just shrugged. And (the guest) just screamed and ran out of the house.

The past three years of Howl-O-Scream have also offered a more intense experience, Alone, in which one to four people experience a haunted house by themselves.

Its not like our other haunted houses, where people are constantly jumping out and scaring you, Swenson said. You actually become a character in the story. It becomes very personal.

He said the smaller group size allows for more elaborate special effects.

It causes the guests to feel a bit more overwhelmed by the number of people in the room with them, he said. Its just them and our performers.

The performers, Swenson said, are carefully vetted from July onward.

We do auditions for all of these people, he said. The July auditions are for people returning we have people who have been with us for all thirteen years, and we also have a lot of people who have been with us for seven or eight years. For the audition, we put them through two improv games to find out how well they can communicate physically what their natural instinct is to startle and reset and then startle again. We then cast for the seven haunted houses and the 18 different roaming hordes.

Howl-O-Scream runs until Oct. 27. Tickets range from $24.99 to $79.99 online and are $79.99 at the gate.