A 'limited edition' of ABC's Primetime starts Tuesday at 10 pmET, with a five-part run of its What Would You Do? programs. A preview of the series aired Friday on 20/20.

Previous incarnations of Primetime:WWYD? aired in 2005 and 2006. An ABC press release says the purpose of WWYD? is to "set up everyday scenarios and then capture people's reactions".

The new batch of one-hour reports, by John Quinones, tackle dilemmas such as:
• If you knew that a friend's spouse was cheating, would you tell your friend?
• As three girls verbally attack another girl in a park, what do people do when they witness the scene?

After Tuesday's premiere, the four subsequent WWYD? segments are scheduled to run weekly on Tuesday nights. Throughout the series, viewers will be able to share comments online at ABCnews.com.

• Related: The Columbia Journalism Review's report on "journalism that tweaks reality, then reports what happens".

• Update: According to preliminary numbers from Nielsen Media Research, the 10 pmET hour of 20/20 (previewing Primetime: WWYD?) finished first in the time period with 8.64 million total viewers. Dateline drew 6.3 million total viewers.