Image634889027094329912Lucy's next episode on Parks and Recreation is "Ron and Diane" Episode 9 which goes to air on 6 December 2012. Here's the synopsis for it

"PARKS AND RECREATION"
"RON AND DIANE"

12/06/2012 (09:31PM - 10:01PM) (Thursday) : RON IS NOMINATED FOR A WOOD-WORKING AWARD - MEGAN MULLALLY ("Will and Grace"), LUCY LAWLESS ("Spartacus") AND CHRISTIE BRINKLEY ("Ugly Betty") GUEST STAR -

Ron (Nick Offerman), Diane (guest star Lucy Lawless), and Leslie (Amy Poehler) attend a wood working awards dinner, after one of Ron's handcrafted chairs is nominated, but the happy occasion is threatened by the arrival of Tammy II (guest star Megan Mullally). Meanwhile, Jerry (Jim O'Heir) hosts a holiday party at his home with his wife (guest star Christie Brinkley), and some of his friends are shocked to find they were not invited. Aziz Ansari, Adam Scott, Chris Pratt, Aubrey
Plaza, Rashida Jones, Retta and Rob Lowe also star.

Source: Spoiler TV

For more about Lucy's role as Diane on Parks and Recreation Season 5 visit the AUSXIP Lucy Lawless Parks and Recreation subsite