 " Galentine 's Day " was written by series co @-@ creator Michael Schur and directed by Ken Kwapis . The episode featured a guest appearance by John Larroquette as Frank Beckerson , the long @-@ lost love of Leslie 's mother , Marlene Knope . When Parks and Recreation co @-@ creator Greg Daniels announced the casting in January 2010 , he described Larroquette 's character as " He 's the one who got away . " " Galentine 's Day " also included an appearance by Pamela Reed , who has played Marlene Knope in several episodes , and the last of a string of slated guest appearances by Justin Theroux as Justin Anderson , a love interest for Leslie . The episode marked the return of Andy 's band , " Mouse Rat " , which was previously featured in the first season finale " Rock Show " . His bandmates are played by Mark Rivers ( drums ) , Andrew Burlinson ( guitar ) and Alan Yang ( bass ) , the latter of whom serves as a screenwriter for Parks and Recreation . 
 " Galentine <a href='null_genetive' title='1'><mark>'s</mark></a>Day " was written by series co @-@ creator Michael Schur and directed by Ken Kwapis . The episode featured a guest appearance by John Larroquette as Frank Beckerson , the long @-@ lost love of Leslie <a href='null_genetive' title='2'><mark>'s</mark></a>mother , Marlene Knope . When Parks and Recreation <a href='uninflect' title='3'><mark>co</mark></a> @-@ creator Greg Daniels announced the casting in January 2010 , he described Larroquette <a href='null_genetive' title='4'><mark>'s</mark></a>character as " He 's the one <a href='null_relcl' title='5'><mark>who</mark></a>got away . " " Galentine <a href='null_genetive' title='6'><mark>'s</mark></a>Day " also included an appearance by Pamela Reed , <a href='null_relcl' title='7'><mark>who</mark></a><a href='been_done' title='8'><mark>has</mark></a> played Marlene Knope in several episodes , and the last of a string of slated guest appearances by Justin Theroux as Justin Anderson , a love interest for Leslie . The episode marked the return of Andy <a href='null_genetive' title='9'><mark>'s</mark></a>band , " Mouse Rat " , which was previously featured in the first season finale " Rock Show " . His bandmates are played by Mark Rivers ( drums ) , Andrew Burlinson ( guitar ) and Alan Yang ( bass ) , the latter of whom <a href='uninflect' title='10'><mark>serves</mark></a> as a screenwriter for Parks and Recreation . 
 Galentine  Day  was written by series co @-@ creator Michael Schur and directed by Ken Kwapis . The episode featured a guest appearance by John Larroquette as Frank Beckerson , the long @-@ lost love of Leslie  mother , Marlene Knope . When Parks and Recreation coed @-@ creator Greg Daniels announced the casting in January 2010 , he described Larroquette  character as " He 's the one got away . " " Galentine  Day " also included an appearance by Pamela Reed , done played Marlene Knope in several episodes , and da last of a string of slated guest appearances by Justin Theroux as Justin Anderson , a luvv interest fa Leslie . The episode marked the return of Andy  band , " Mouse Rat " , which was previously featured in tdafirst season finale " Rock Show " . His bandmates r played by Mark Rivers ( drums ) , Andrew Burlinson ( guitar ) and Alan Yang ( bass ) , the latter of whom serve as a screenwriter for Parks and Recreation .