The grand larceny trial of Mayor Michael Bloomberg's former political aide took a dramatic turn Tuesday, when John Haggerty's former lover landed on the witness stand, but the judge did not allow the jury to hear that the affair was extramarital. NY1's Grace Rauh filed the following report.

A case filled with political intrigue now has a romantic plotline as well.

A day after Mayor Michael Bloomberg landed on the witness stand, his former campaign aide, Fiona Reid, found herself at Manhattan criminal court as well.

Reid was testifying in the grand larceny and money laundering case against John Haggerty. The two had an affair during the mayor's re-election campaign in 2009.

At the time, Reid was the Bloomberg campaign's chief financial officer. Haggerty, who is married, was hired to run a ballot security operation.

Prosecutors say the $1.1 million operation never materialized and that Haggerty stole most of the money and used it to buy a house. Reid, Haggerty's mistress at the time, reviewed his budget for poll watching before the payment went through.

Reid said she did not know Haggerty planned to buy a house with the money.

Visibly nervous on the witness stand, Reid said her relationship with John Haggerty began in September 2009 and ended in January 2010, when the investigation began. She said her lawyer advised her to end it.

Her testimony did not produce the fireworks some were expecting. The judge would not allow any mention of the fact that Haggerty was married and cheating on his wife during his relationship with Reid.

Reid identified Haggerty in the courtroom, but that was the extent of their interaction.

"We were pleased with the judge's rulings today. I think the judge was very even-handed, was very careful in his rulings today about the admissibility of certain evidence. So, we're pretty content at this point," said Dennis Vacco, Haggerty's attorney.

Haggerty faces up to 25 years in prison if convicted.