19 Timeslots, Tuesday 9PM

Across the last three years, it's been a timeslot owned by eccentric geniuses, first Hugh Laurie's House and then Simon Baker's The Mentalist, but they're both out of the picture in fall '09, while three networks go the reality route.

ABC: The alphabet has relied on Dancing with the Stars in this timeslot, first the last half hour of the performance show in fall '06 leading into failed Ted Danson comedy Help Me Help You, then the results show in future cycles. As is the case on Monday, the adventure comes in the winter. ABC brought another comedy bomb to the 9:00 hour in November '06 in Big Day, then eventually found considerably more success with February '07 effort Primetime: The Outsiders. More comedy disasters filled the slot during the '07-'08 hiatus starting with repeats of According to Jim and eventually bringing in originals alongside burnoffs of fall '07 failure Carpoolers. The '08-'09 Dancing break saw yet more Jim and then a run for NBC import Scrubs which started surprisingly well (over a 3.0 demo) but lost steam by the end. It'll be Dancing results once again in '09-'10. The two cycles averaged a 4.1 and 3.6 in Tuesday originals last season. Returning comedies Scrubs and Better Off Ted are initially slated to fill the hiatus. Both comedies have seen some time in this slot during the summer including some Ted originals which had completely awful (usually sub-1 demo) results.

CBS: This timeslot was the home to the first three seasons of military drama The Unit starting in spring '06. The third season was only 11 episodes due to the writer's strike and so the slot was one of the homes for the strike edition of Big Brother and then a tryout for legal drama Shark which skewed too old on Tuesday and was axed. Mediocre results from the Unit in fall '07 led to an injection of new blood for fall '08 in drama The Mentalist. It was a smash success and aired there all of last year but is being moved to Thursday as a seeming heir apparent to CSI's Thursday 9:00 home so for fall '09 it's newbie NCIS:LA, a spinoff of its 8:00 lead-in.

FOX: The original home of medical drama House, the net moved House to 8:00 in fall of '06 so it could lead into newbie Standoff at 9. When Standoff had a tepid start it was bumped to 8 and House returned to 9, where it stayed until winter of '08 when the net shifted its Bones/House night to Monday and brought in a writer's strike edition of Hell's Kitchen to air after American Idol. New Amsterdam and 'Til Death got brief tryouts in the slot in between the House move and the Kitchen arrival. In fall '08 House returned to 8 to lead into newbie Fringe which lasted for the full season in the slot, staying there even after Idol arrived. Plenty of two-hour Idols air their second hour in this slot as well. But the fall '09 plan is the second half of a two-hour So You Think You Can Dance. New drama Past Life will get a run post-Idol in the spring.

NBC: In fall '06 NBC kicked off its "Law & Order Tuesdays" in this hour with Criminal Intent in what would be its final first-run season on broadcast. In fall '07 The Biggest Loser took up residence in the 9:00 hour where it has pretty much stayed ever since, with the exception of some Saturday Night Live encores near the end of the '07-'08 season. TBL returns for fall '09, though it is slated at midseason to share this hour with new comedy 100 Questions. It's not the first time NBC has tried shortening the show (comedy Kath & Kim was supposed to air at 9:30 in fall '08 but shipped to Thursdays before the season began) so we'll see how it goes.

CW: In fall '06 the CW aired UPN import Veronica Mars to unsatisfactory results. It was canned at season's end in favor of drama Reaper which stayed there for all of '07-'08 and eked out a second season despite not skewing the way the net wanted. However it was slated for midseason and the CW went with another new drama Privileged in the slot for fall '08. Privileged saw only a small expansion on its original 13-ep order and was cleared out by winter so that 90210 could air in the timeslot, away from American Idol. 90210 shifts back to 8:00 in fall '09 while yet another remake Melrose Place will lead out of it.

Cable Notables: Syfy offers Scare Tactics, a reality effort that took a 2.5 year hiatus between its second and third seasons.