The two-part, four-hour Internal Affairs (CBS Sunday...

The two-part, four-hour Internal Affairs (CBS Sunday and Monday at 9 p.m.), a sequel to the 1985 “Doubletake,” stars Richard Crenna as a New York City police detective attempting to solve a bizarre murder case while ferreting out corruption in the department.

The Great Escape II: The Untold Story (NBC Sunday and Monday at 9 p.m.), also four hours and airing in two parts, picks up where the popular 1963 Steve McQueen movie left off. Christopher Reeve and Judd Hirsch are among a group of former World War II POWs who return to Nazi Germany to search for the killers of 50 fellow prisoners.

Down and Out in Beverly Hills (ABC Sunday at 9 p.m.), Paul Mazursky’s inspired reworking of the old French play filmed by Jean Renoir as “Boudu Saved From Drowning,” drops Nick Nolte’s gloriously iconoclastic vagabond into the nouveau riche household of businessman Richard Dreyfuss and his wife Bette Midler, the Beverly Hills housewife supreme. This 1986 film, one of the best American comedies of the ‘80s, is hilarious but it also is surprisingly touching.

Randal Kleiser’s fine 1980 remake of The Blue Lagoon (Channel 5 Monday at 8 p.m.) succeeds in involving us for two hours with a couple of kids (Brooke Shields, Christopher Atkins) stranded on a tropical isle and presents their coming of age--in ignorance of the facts of life--with honesty but without exploitation.

Once Bitten (Channel 13 Monday at 8 p.m.) is a sly and amusing 1985 comedy starring Lauren Hutton as a gorgeous vampire who’s finding it increasingly difficult to meet young male virgins whose blood is essential to preserving her youth.

John Hughes’ 1985 The Breakfast Club (Channel 5 Tuesday at 8 p.m.) takes place on a wintry March morning at a suburban high school in Illinois where five radically disparate kids (Anthony Michael Hall, Emilio Estevez, Ally Sheedy, Molly Ringwald and Judd Nelson), condemned to all-day detention, get to know each other in the course of a long day. A kind of have-it-both-ways attempt to fuse “Who’s Afraid of Virginia Woolf?” with “Animal House,” the movie is too schematic for its own good and needs a more honest sense of rebellion, something looser and wilder.

Beginning Tuesday at 8 p.m. (and continuing through Friday), Channel 13 brings back The Godfather: The Complete Novel for Television, an overwhelming instance of the whole being greater than the sum of its parts.

About Last Night (Channel 5 Wednesday at 8 p.m.) has taken playwright David Mamet’s taut, vitriolic, dazzlingly funny valentine to the one-night stand and turned it into a hilarious, insightful, bawdy Baedeker to The Relationship today, post-sexual revolution but pre-AIDS. The 1986 movie stars Rob Lowe and Demi Moore, who are thrown by their playful, above par-for-the-course one-night stand. Their unexpectedly burgeoning love also throws their respective best friends, a foul-mouthed James Belushi and sharp-tongued Elizabeth Perkins (too inexplicably unsympathetic for the film’s good). But Lowe and Moore make us care about them--more than we expected to.

Ladykillers (ABC Wednesday at 9 p.m.) is a new TV movie starring Marilu Henner, Susan Blakely, Thomas Calabro and Lesley-Anne Down in a thriller about a psychotic killer whose victims are male strippers.

The ultra-violent 1983 Bad Boys (Channel 5 Thursday at 8 p.m.) tells us nothing new about juvenile prisons, but it does have Sean Penn, who manages to overcome his lack of revealing lines and a glower into something approaching a characterization.

WarGames (Channel 5 Friday at 8 p.m.) is an ingenious winner in which high school computer whiz Matthew Broderick (who has an equally engaging girlfriend, Ally Sheedy) blunders into a game, Global Thermonuclear War, with the Defense Department’s computer, which keeps ticking away after Broderick quits. This is a terrific premise, and writers Lawrence Lasker and Walter F. Parkes and director John Badham and their splendid cast make the most of it.

Saturday brings two nifty vintage Clint Eastwood movies, Coogan’s Bluff (Channel 5 at 8 p.m.) and Joe Kidd (Channel 13 at 10 p.m.).