Mark Margolis Mark Margolis is an actor who portrayed Doctor Nel Apgar in the third season episode . He is the father of and guest star Morgan Margolis . Coincidentally , both he and his son appeared in episodes in which Craig Richard Nelson guest starred . Margolis had a recurring role on the hit CBS action drama " The Equalizer " , which starred Robert Lansing and Keith Szarabajka . Margolis also appeared with Lansing and Szarabajka , as well as Anthony Zerbe , in the 1988 " Equalizer " TV movie , " Memories of Manon " . The following year , he appeared in a first season episode of " Quantum Leap " , starring Scott Bakula and Dean Stockwell . In 1992 , Margolis appeared on " " as an illegal gun runner who shoots Detective , played by TNG guest star Paul Sorvino . Margolis made two more appearances on " Law & Order " as different characters ( in 1997 and 2001 ) . From 1998 through 2003 , Margolis made recurring appearances as Antonio Nappa on the HBO series " Oz " . He has also appeared on such shows as " The Practice " ( with Bill Smitrovich ) , " Sex and the City " ( starring Kim Cattrall ) , and " The Black Donnellys " ( starring Kate Mulgrew ) . One of Margolis ' earliest films was the 1977 drama " Short Eyes " , starring Bruce Davison . Margolis later acquired some recognition for his role as Alberto The Shadow in the 1983 film " Scarface " , which co - starred F . Murray Abraham , Harris Yulin and Gregg Henry . Margolis ' other motion picture credits throughout the 1980s include " The Bedroom Window " ( 1987 , with Wallace Shawn , Brad Greenquist , and Leon Rippy ) , " The Secret of My Succe $ s " ( 1987 , with Bruce McGill ) , and " Glory " ( 1989 , with Bob Gunton , Cliff DeYoung , Richard Riehle , and star Ethan Phillips ) . In 1994 , he had a brief but memorable role in " Ace Ventura : Pet Detective " , playing Ace Ventura ' s suspicious landlord , Mr . Shickadance . That film also featured Noble Willingham and Tiny Ron . Other films include " 1492 : Conquest of Paradise " ( 1992 , with Frank Langella ) , " Absolute Power " ( 1997 , with Penny Johnson ) , " The Thomas Crown Affair " ( 1999 ) and " Hannibal " ( 2001 ) with David Andrews and Francis Guinan the latter of whom both played FBI agents . Margolis has also starred in all three feature films from director : 1998 ' s " Pi " , 2000 ' s " Requiem for a Dream " ( with Christopher McDonald ) , and 2006 ' s " The Fountain " ( with Stephen McHattie and Donna Murphy ) . In 2003 , he appeared in an uncredited role in the comic book action film " Daredevil " , which also featured Erick Avari , Leland Orser , and ( in the Director ' s Cut ) Jude Ciccolella . The following year he was seen in the comic drama " House of D " , starring Anton Yelchin and Frank Langella . He more recently appeared in the acclaimed drama " Gone Baby Gone " with Titus Welliver . His upcoming films include the war drama " Defiance " and Darren Aronofsky ' s " The Wrestler " . In 2009 - 2011 , he appeared in " Breaking Bad " , playing the uncle of Raymond Cruz ' character , and which also guest - starred John de Lancie . He reprised his role in the prequel series " Better Call Saul " , opposite Cruz , Jonathan Banks , Patrick Fabian , and Michael McKean .