A video allegedly showing R Kelly involved in sex acts with an underage girl has been shown to jurors at his trial in Chicago.
Cook County prosecutor Shauna Boliker warned the jury they would see footage of an "underage child performing sex acts that you have never seen before".
But the R 'n' B star's legal team claims that the video depicts neither Kelly nor the alleged victim.
The I Believe I Can Fly star is accused of filming himself engaging in sex acts with a girl who prosecutors say may have been as young as 13 at the time.
Ms Boliker told the members of the jury they would have to see "the sex acts he commands her to do".
"Acts you have never seen before. Vile, disturbing and disgusting sex acts, actions that were choreographed, produced and starred in by Robert Kelly," she added.
However, Kelly's lawyer Sam Adam Jr described the tape as "at best a copy of a copy of a copy" and claimed that neither the FBI nor "a single witness" could conclusively identify his client as the man in the tape, according to the Associated Press news agency.
Mr Adam also pointed out that while Kelly has a "significant" coin-sized mole on his back - going so far as to show the jury pictures of the singer's blemish - the man in the footage does not appear to have a mole.
The alleged victim, now 23, testified before a grand jury in 2002 that she was not the girl in the videotape.
The trial, which has been repeatedly delayed, continues.