Carolyn Reynolds' story is the stuff of nightmares, a tale that's in no way hiss-terical.

As she settled into bed for an evening of Q&A on the telly this week, she felt something start to move beneath her head.

"I thought to myself, 'God, there's plenty of mozzies around tonight', because I could hear something vibrating or hissing."

The bush education instructor from Lake Bennett, south of Darwin, said she held her breath as she began to turn the pillow over.

"I peeked beneath my pillow and jumped out of bed as fast as I possibly could," she told ABC Radio Darwin's Jo Laverty.

"At first I thought it was a king brown."

Upon closer inspection, however, Ms Reynolds, who is a biologist by trade, was able to identify the snake as a flaky grey.

Ms Reynolds says her family is unlikely to visit the NT ever again after hearing her story. ( Supplied: Carolyn Reynolds )

Keeping warm during the dry

As temperatures begin to cool for the dry season, Ms Reynolds said snakes tended to surface around this time of year.

"Snakes are on the move to find a warm place to sleep; it seems my bed was definitely warmer than outside.

"I caught the snake [in a pillow case] and organised to take it up to the wildlife park to see if they wanted a very pretty specimen.

"As long as you are calm, cool and collected, the creature will not come after you."

Ms Reynolds said her unusual bedtime encounter had prompted multiple jokes from family in the United Kingdom.

"I have been on my own for the past 20 years, so my family have been sure to make a great big joke about having a 'snake' in the bed."

She said while living in remote areas of the Territory had prepared her for the unexpected, this particular incident would go down in history.

"A snake by your head is an enlightening moment."