Season 27

Bette Midler ; Beth Behrs (2 Broke Girls (2011) [/title/tt1845307/]. Also: "Paw-fect Pet Week" concludes with advice on traveling with pets.

Jeff Daniels (Dumb and Dumber To (2014) [/title/tt2096672/]); Eddie Redmayne (The Theory of Everything (2014) [/title/tt2980516/]). Also: Dr. Jennifer Jellison' with pet first aid.

Anne Hathaway (Interstellar (2014) [/title/tt0816692/]); Kristen Johnston (The Exes (2011) [/title/tt1830888/]).

Matthew McConaughey (Interstellar (2014) [/title/tt0816692/]); Felicity Jones (The Theory of Everything (2014) [/title/tt2980516/]). Also: dog trainer Andrea Arden gives shelter dogs a makeover.

Jessica Chastain (Interstellar (2014) [/title/tt0816692/]); Michael C. Hall (Cold in July (2014) [/title/tt1179031/]). Also: "Paw-fect Pet Week" kicks off with celebrity dog groomer Jorge Bendersky .

A Halloween extravaganza, including a look at characters from pop culture; an audience costume contest.

Rene Russo (Nightcrawler (2014) [/title/tt2872718/]); Caroline Wozniacki . Also: Sam Hunt performs.

Lucy Liu (Elementary (2012) [/title/tt2191671/]); Deion Sanders . Also: top Halloween moments.

Amy Poehler ; Joey McIntyre (The McCarthys (2014) [/title/tt3434378/]). Also: top Halloween moments.

Emma Thompson ; Stanley Tucci .

Howie Mandel ; Gretchen Mol (True Story (2015) [/title/tt2273657/]).

Mark Consuelos (Alpha House (2013) [/title/tt3012160/]); Jessica Capshaw (Grey's Anatomy (2005) [/title/tt0413573/]). Also: Annie Lennox performs.

Hugh Jackman (X-Men: Days of Future Past (2014) [/title/tt1877832/]); Danai Gurira (The Walking Dead (2010) [/title/tt1520211/]).

Keanu Reeves (John Wick (2014) [/title/tt2911666/]); Tom Cavanagh (The Flash (2014) [/title/tt3107288/]). Also: singer-songwriter Kiesza .

Naomi Watts (St. Vincent (2014) [/title/tt2170593/]); Jenny McCarthy (I)

Guest co-host David Muir ; Bridget Moynahan (Blue Bloods (2010) [/title/tt1595859/]); Jason Schwartzman .

Guest co-host Mark Consuelos ; Julianne Hough (Dancing with the Stars (2005) [/title/tt0463398/]); Josh Radnor . Also: Paloma Faith performs.

Guest co-host Josh Groban ; Emma Stone (Birdman or (The Unexpected Virtue of Ignorance) (2014) [/title/tt2562232/]); Suzanne Somers . Also: Neon Trees perform.

Michael Keaton (Birdman or (The Unexpected Virtue of Ignorance) (2014) [/title/tt2562232/]); Minnie Driver (About a Boy (2014) [/title/tt2666270/]).

Neil Patrick Harris ; Maura Tierney . Also: Jessie J performs.

Jeremy Renner (Kill the Messenger (2014) [/title/tt1216491/]); Jennifer Morrison (Once Upon a Time (2011) [/title/tt1843230/]).

Reese Witherspoon (Wild (2014) [/title/tt2305051/]); Steve Carell (Alexander and the Terrible, Horrible, No Good, Very Bad Day (2014) [/title/tt1698641/]); Emmy Rossum (Shameless (2011) [/title/tt1586680/] and (You're Not You (2014) [/title/tt1198156/]).

Robert Downey Jr. (The Judge (2014) [/title/tt1872194/]); Alan Cumming (The Good Wife (2009) [/title/tt1442462/]). Also: Hilary Duff performs.

Ted Danson (CSI: Crime Scene Investigation (2000) [/title/tt0247082/]); Martina McBride . Also: La Roux perform.

Matthew Broderick ; Ansel Elgort ("Men, Women and Children").

Claire Danes (Homeland (2011) [/title/tt1796960/]); Emily Ratajkowski (Gone Girl (2014) [/title/tt2267998/]).

Jennifer Garner (Alexander and the Terrible, Horrible, No Good, Very Bad Day (2014) [/title/tt1698641/]); Blake Shelton .

Tyler Perry . Also: Ana Gasteyer performs.

Mark Harmon (NCIS (2003) [/title/tt0364845/]); Taye Diggs (The Good Wife (2009) [/title/tt1442462/]). Also: Melissa Etheridge performs.

Ben Affleck . Also: Bryan Adams performs.

Andy Samberg ; Omar Epps (Resurrection (2013) [/title/tt2647586/]. Also: a performance by indie-pop band, AJR .

Sofía Vergara (Modern Family (2009) [/title/tt1442437/]); Terry Crews (Who Wants to Be a Millionaire (2002) [/title/tt0321019/]).

Denzel Washington; Rosamund Pike.

Kerry Washington (Scandal (2012) [/title/tt1837576/]); Bill O'Reilly (The Factor (1996) [/title/tt0284767/]).

James Spader; Jim Caviezel. Also: Mary Lambert performs.

Tina Fey ("This Is Where I Leave You"); Luke Wilson ("The Skeleton Twins").

Liam Neeson; Tea Leoni; magician Mat Franco, winner of "America's Got Talent".

Julianna Margulies; Jeff Probst; chef Eric Ripert.

Rose Byrne (Annie (2014) [/title/tt1823664/] and This Is Where I Leave You (2014) [/title/tt1371150/]); Kira Kazantsev , Miss America 2015. Also: Jason Mraz performs.

Octavia Spencer; Dylan O'Brien; Lara Spencer.

Connie Britton (Nashville (2012) [/title/tt2281375/]); Mindy Kaling (The Mindy Project (2012) [/title/tt2211129/]).

Katharine McPhee; Taraji P. Henson.

Ashley Judd; Justin Long; Jimmie Johnson.

Jason Bateman; Jenna Dewan-Tatum.

Steve Buscemi; Max Greenfield.

Kevin Kline; Juliette Lewis. Also: Kelly and Michael compete against Nick Carter and Jordan Knight in a "tough mudder" competition.

Ray Liotta; the winner of "So You Think You Can Dance". Also: Counting Crows perform.

Liev Schreiber (Ray Donovan (2013) [/title/tt2249007/]); Jesse Metcalfe (Dallas (2012) [/title/tt1723760/]). Nick Carter and Jordan Knight perform.

Mandy Patinkin (Homeland (2011) [/title/tt1796960/]); anchorman David Muir (ABC World News Tonight with David Muir (1953) [/title/tt0184090/]).

The season 27 opener includes an interview with Lea Michele . Also: tips for healthy school lunches.