INTELLIGENT performances from ever-reliable Gene Hackman (see him tomorrow too in No Way Out ) and Joanna Cassidy (Wheels of Terror ) lend strength to The Package (World, 9.30pm, Original Running Time 108 mins), a political thriller which starts well but loses credibility somewhere en route to the final credits. The story begins in Berlin at the end of the Cold War, as the superpowers prepare to sign a nuclear disarmament treaty. Hackman plays a career army sergeant assigned by a desk-jockey colonel (John Heard) to deliver court-martialled soldier (Tommy Lee Jones) to the US. Jones escapes and Hackman discovers he's the pawn in the centre of a political conspiracy. He enlists the help of his ex-wife (Cassidy), a Lt-Col at the Pentagon, to work out what's really going on. There are some good action sequences and the plot begins well, but this thinly-disguised Red-threat movie hits the ''Oh, come on '' button too hard. NOW that Cheers has finished in the US, The Simpsons (World, 9pm) has taken its place as the in show for stars' guest spots - well, guest voice anyway. Hip-swivelling grandpa, Tom Jones, the Welsh songster at whom it's not unusual for women to throw their personal garments is the guest voice this week. He's kidnapped by Homer's boss, who's fallen in love with Marge and wants old Tom to serenade her. FOR something completely different try Tales from the Map Room (BBC, 9.25pm), which dramatically recreates significant moments from cartographic history. Doesn't sound riveting, but it is. The first episode, Plumb Pudding in Danger is named after an 18th-century cartoon which depicted Napoleon for France and Pitt for Britain blithely carving up a plum pudding of the world. Forty per cent of the world's boundaries referred to in that satireremain today. Maps also aided colonisation: English maps of North America invented ''New England'', replacing native names with English ones and effectively wiping out an entire culture. BOTH director Kevin Reynolds and his actor pal Kevin Costner were just beginning to show their true worth in the 1985 coming-of-age movie Fandango (Pearl 12.10am, ORT 92 mins). Costner's performance holds together the patchy story (based on Reynolds' student film Proof ), which concerns five college pals indulging in one last fling before facing up to the responsible realms of ''real life''. Judd Nelson and Glenne Headly also star. Incidentally, it was Steven Spielberg who paid for Proof 's expansion to feature length. I GUESS the umpteenth repeat of Police Academy (Pearl 9.30pm, ORT 92 mins) must be mentioned. This is the original tale which launched a thousand (well, six) sequels. The jokes are racist, sexist, fat-ist, yokel-ist, ugly-ist, and now they're even out of date, so those of politically sound nature should steer well clear. However, anyone willing to don their Carry On hat for the night could find themselves all of a-titter. STOP PRESS: TVB Pearl have secured rights to Thatcher: The Downing Street Years, a four-part BBC production about the former prime minister's newly published and controversial memoirs. TVB spokesperson Veronica Chiu said the content of the series is ''being kept very hush, hush [and is] embargoed until the first programme is broadcast in the UK on October 21''. Pearl will show that episode here just two days later on October 23 (8.30pm). The series includes interviews with the Iron Lady herself, as well as some of the more disgruntled subjects of her book, which has already attracted court action in Britain.