She’s afraid of the dark.

Who would have thought that?

Theresa Caputo, star of TLC’s hit television show “Long Island Medium,” will be back April 5 for her fourth appearance at Mohegan Sun.

Asked what fans may be surprised to know about her, Caputo matter-of-factly replied in a telephone interview that she has always been frightened by the dark.

“I sleep with some kind of light on,” she said.

That is surprising, considering she has made a career out of communicating with the dead.

The reality television star, who is also an author and mother who has recently separated from her husband of 28 years, is a lifelong resident of Hicksville, Long Island.

She was 4 when she first started seeing, feeling and sensing “Spirit,” she said, but it wasn’t until she was in her 20s that she learned to communicate “with souls in heaven.”

On her reality television show, she meets with clients who want to connect with deceased loves ones, or she randomly conveys messages to complete strangers she encounters when "Spirit" compels her to.

Her three past shows at Mohegan Sun have all been sell-outs, and that’s anticipated when she returns next week.

At the Uncasville casino, her appearances are held in the Theatre at Mohegan Sun Arena, a smaller venue set in the cavernous space where basketball and bull-riding events are held and superstars like Cher have appeared. For Caputo, the arena is pared down to seat about 4,000 — a more intimate setting for “Spirit” to come calling.

“Honestly, it’s no different for me when I walk into a room with five or 5,000 people,” said Caputo. “There’s only so many souls I can channel in a two-hour period.

“And in a large space, I’m not on the stage, I’m walking around and Spirit is steering me in my 7-inch heels.”

Caputo, 51, is known for her long and perfectly painted fingernails, coifed hair, and high heels.

She has explained that “Spirit” speaks to her by sending intuitions, signs and symbols that allow her to connect the dead with the living. She described it as almost “a sixth sense — a kind of feeling and knowing."

“When I get information, it feels like a very strong intuition or recall,” she said.

Decades ago, she suffered from anxiety and unsuccessfully tried to work through it on her own and with help from a therapist. Then, her mother introduced her to a spiritual healer named Pat Longo, and Caputo found her calling.

“After just one session, she told me that I was suppressing Spirit’s energy, which caused a lot of my anxiety, and helped me learn to channel Spirit through my chakras and release it with my words,” said Caputo. “I began to heal and come into my own.”

There are skeptics, and Caputo said she knows not everyone believes that what she does is real or even possible.

Raised a Roman Catholic, she said early on she had her own misgivings about communicating with the dead because she believed it conflicted with her faith.

Then, she said, she realized that her ability was a gift from God, and with it, she was able to do good.

Her messages are always positive, oftentimes assuring the living that their deceased loved ones are pain-free, or at peace, or that the living could not have done anything more to prevent the death.

“When I embrace my gift, I put out to Spirit that I only want positive things. I want to help people move on,” she said.

Asked if she communicates with her own dead, Caputo said she has received messages from her grandparents and her late American bulldog, Petey.

“My beloved Petey visits me,” she said.

Oftentimes when she is channeling messages, Caputo will comment to the person who is receiving her reading, “You can’t make this stuff up.” She says it when the living recipient is wowed by the message, convinced Caputo couldn’t have known beforehand what she is sharing.

It might be that the living has gotten a tattoo to honor the deceased and the tattoo isn’t readily visible, or that they’ve sold property, or remarried, or done something else that Caputo wouldn’t know of.

"Spirit" will send a message through Caputo that the deceased knows about the tattoo, or the property sale or the move, and that they approve of it.

Those revelations typically bring exclamations or tears, providing assurances to the living that the deceased is watching from afar.

“I am the first one to say that what I do is crazy,” said Caputo. “But it is impossible for me to know certain things about people and, in 30 seconds, to give a life-saving message.”

Sometimes the living agonize that they could have done more to prevent a death, maybe stop someone from driving or force someone to see a doctor.

“It’s easy to beat ourselves up,” said Caputo, explaining that "Spirit" sometimes just wants the living to know that, regardless of what actions they took, they couldn’t have prevented the death.

“I just know that one sentence from Spirit is better than years of therapy,” she said.

Caputo’s popular television show first aired in 2011 and is still enticing fans. She is booked more than two years out for personal readings and has a waiting list, with no guarantee of ever getting on her calendar.

She believes that she has a gift and that what she does is good and healing.

“Souls on the other side, they band together and have me deliver the message,” she said. “And it can bring incredible peace.”

If you go

Who: Theresa Caputo

Where: Mohegan Sun Arena

When: 7:30 p.m. April 5

Tickets: $39.75-$89.75

Visit: mohegansun.com