In The Sixth Sense, Malcolm and his wife discover an intruder in their home to be one of Malcolm's former patients, Vincent Grey.
Vincent is standing in Malcolm's bathroom dressed only in his underwear to confront Malcolm.
We see Vincent's clothes on the bathroom floor, so he removed them after entering the home.
What was the purpose of Vincent removing his clothes after he entered Malcolm's home? Is this ever explained?
Johnny has nicely answered that it was to show his mental state but I feel it also helps to show his physical state, as he was physically not looking well and we can see some scars also on his body which look fresh, we saw scars on Cole later too. This indicates that they might also be given by ghosts to Vincent.
Behind the scene, it was the idea of the actor himself (From USA Today:
During a film workshop with Willis and Olivia Williams (Malcolm's wife, Anna), Wahlberg proposed playing Gray nude rather than the goth clothing detailed in the script.
"If Vincent is coming to stop his suffering and end his own life, then why is he wearing anything? To me, he strips down and is in the bathroom fully naked, clothes on the floor," says Wahlberg. "Bruce thought that was awesome and pitched the idea to M. Night, who was like, 'That's insane. I love it.' "
Wahlberg now had to fully look the part. "I had to become emaciated and change my physical appearance."
"I was so hungry. I was depressed," he says. "I cut off my life to get ready for the role."
Five weeks later, he showed up to "The Sixth Sense" set having dropped 43 pounds to a scary 139. "I passed Night and he didn’t recognize me. He just walked right past," says Wahlberg.
Sent to wardrobe, the actor found out that the film would be rated PG-13, so that would require clothes after all.
"I was like 'Oh (expletive), I just lost 40 (expletive) pounds. And now I have to just wear clothes.' I was so conflicted," says Wahlberg. He struck a quick compromise: wearing Vincent's "tidy whiti" underwear.
"I asked to make (the underwear) look like I hadn’t changed them in, like, two years," he says. "They soiled them up. That became the wardrobe."
The correct answer, unfortunately, is "No". They never explain it in the movie, but the idea they most convey is that Malcolm "stripped" Vincent of his mental stability. It's clear that Vincent is unhinged, and we find out later in the movie that it's because Vincent "saw dead people". This is what tied Malcolm to Cole as well, and why Vincent must stay to eventually help Cole.
