MARK HARMON is best known for his work as Special Agent Leroy Jethro Gibbs on NCIS.

However, he has a string of film credits to his name. Among them is the Disney comedy Freaky Friday in 2003 – and in tonight’s episode he’s reunited with his co-star Jamie Lee Curtis.

She stars as Samantha Ryan, the director of a division specialising in psychological warfare, and someone who shares more than a little bit of chemistry with Gibbs. She is put in contact with the team following a botched burglary, in which a pair of intruders opened fire on someone they later claim was already dead.

It emerges that the victim is Dr Robert Banks, who worked as a naval reservist and psychologist, with high-level Pentagon clearance. This puts the case squarely in NCIS’s remit.

After examining the body, Ducky finds marks around his neck consistent with a hanging. However there’s also the small matter of a bullet wound left by the burglars.

Which injury actually killed the man?

As Ducky gets busy finding out, Ziva makes a surprising discovery on the dead man’s phone – he was called four times by Dr Cranston, the older sister of the deceased NCIS agent Caitlin Todd.

Cranston is adamant that if he was hanged, it wasn’t a suicide, and fills Gibbs in on his background. It seems that not only was he recently divorced, but he was also under a tremendous amount of pressure at work, where he was working on a top-secret project involving mind games designed to confuse and manipulate enemies.

It seems only fitting, then, that “chief brain-gamer” Ryan be the one to assist the team. She knows the deceased well, having been to college with Banks and Cranston. She also reveals that she and Cranston had both slept with Banks. It comes as a shock, then, when they discover that someone seems to have been trying to drive the victim steadily insane, using his own department’s technology, no less.

Curtis enjoyed the role. “We’re both very happily married people, we’ve been in a film together and we knew each other a long time ago. So I’m very fond of him, and he’s fond of me, and that’s just a given. So I’m not going to lie to you and say that this is a horrible, difficult job to play with him,” she says.