US Release date: 15 October 1948
First Melbourne Saturday Suburban: 8 July 1950
Genre: Adventure Country: USA.
Running time: 75 minutes.
Director: Jack Bernhard
Cast: Virginia Grey, Phillip Reed & Richard Denning
Australian Distributor: 20th Century Fox
Melbourne Premiere Venue: One week at Hoyts Lyceum Theatre from 9 June 1950 with Esther Waters as support.
Suburban Release Type: Hoyts Memorial 8-W-1
Rankings
| Rank | ||
| EF Points | 129 | 165 |
| EF PPE | 3.39 | 161 |
| Metres Travelled | 408,234 | 236 |
| Average MT | 10,743 | 112 |
| Engagements | 38 | 243 |
| Slots | 40 | 273 |
| Weeks | 2 | 238 |
| Weeks as % of engagements | 5.26% | 264 |
| Saturdays | 9 | 231 |
| Sats as % of engagements | 23.68% | 257 |
| Tuesdays | 27 | 39 |
| Tues as % of engagements | 71.05% | 30 |
| First billed | 31 | 131 |
| Second billed | 7 | 209 |
| Feature only | 0 | 34* |
Hoyts Ratios
| Engagements weeks 1-10 | 37 |
| Ratio | 97.37% |
| Difference to chain ratio | 5.01% |
| Eng weeks 11-26 | 1 |
| Ratio | 2.63% |
| Difference to chain ratio | -2.76% |
| Eng weeks 27-52 | 0 |
| Ratio | 0.00% |
| Difference to chain ratio | -2.24% |
| Hoyts eng | 21 |
| Ratio | 55.26% |
| Difference to chain ratio | -10.52% |
| Independent eng | 6 |
| Ratio | 15.79% |
| Difference to chain ratio | 4.29% |
| Suburban eng | 11 |
| Ratio | 28.95% |
| Difference to chain ratio | 6.23% |
NOTES: SFX spectacle was picked up by Fox for its Australian release and hit the Tuesday night beat for Hoyts with Homicide as its support (plus a handful of Saturdays). I am guessing that, based on content alone, it would have been popular with the kids on the Saturday matinee circuit.
Unknown Island engagements
| SUBURB | VENUE | CHAIN | DATE | W | D | B | CO-FEATURE |
| Collingwood | Austral | Suburban | 8/7/50 | 1 | S | 1 | The October Man |
| Prahran | Empress | Hoyts | 8/7/50 | 1 | S | 1 | Blondie Hits the Jackpot |
| Albert Park | Park | Hoyts | 8/7/50 | 1 | T | 1 | Homicide |
| Fitzroy | Regent | Hoyts | 8/7/50 | 1 | T | 1 | Homicide |
| North Fitzroy | Merri | Hoyts | 8/7/50 | 1 | T | 1 | Homicide |
| Port Melbourne | Eclipse | Hoyts | 8/7/50 | 1 | T | 1 | Homicide |
| Richmond | Cinema | Hoyts | 8/7/50 | 1 | T | 1 | Homicide |
| St.Kilda | Memorial | Hoyts | 8/7/50 | 1 | W | 1 | Blondie Hits the Jackpot |
| Richmond | Globe | Suburban | 15/7/50 | 2 | S | 1 | Homicide |
| Brunswick | Alhambra | Hoyts | 15/7/50 | 2 | S | 1 | Blondie Hits the Jackpot |
| Coburg | Town Hall | Hoyts | 15/7/50 | 2 | S | 1 | Blondie Hits the Jackpot |
| Ascot Vale | Ascot | Suburban | 15/7/50 | 2 | T | 1 | Homicide |
| Camberwell | Rivoli | Suburban | 15/7/50 | 2 | T | 1 | Homicide |
| Newmarket | Newmarket | Suburban | 15/7/50 | 2 | T | 1 | The October Man |
| Northcote | Northcote | Suburban | 15/7/50 | 2 | T | 1 | Homicide |
| Ascot Vale | Waratah | Hoyts | 15/7/50 | 2 | T | 1 | Homicide |
| Essendon | Plaza | Hoyts | 15/7/50 | 2 | T | 1 | Homicide |
| Essendon | Circle | Hoyts | 15/7/50 | 2 | T | 1 | Homicide |
| Glenhuntly | Glenhuntly | Hoyts | 15/7/50 | 2 | T | 1 | Once Upon a Dream |
| Thornbury | Regent | Hoyts | 15/7/50 | 2 | T | 1 | Homicide |
| Footscray | Barkly | Hoyts | 22/7/50 | 3 | S | 1 | Floodtide |
| Carnegie | Carnegie | Hoyts | 22/7/50 | 3 | T | 1 | It’s Not Cricket |
| Glenferrie | Palace | Hoyts | 22/7/50 | 3 | T | 1 | It’s Not Cricket |
| Preston | Circle | Hoyts | 22/7/50 | 3 | T | 1 | Homicide |
| Fairfield | Fairfield | Suburban | 29/7/50 | 4 | T | 1 | The October Man |
| North Fitzroy | Palace | Suburban | 29/7/50 | 4 | T | 1 | Homicide |
| Brunswick | Lygon | Hoyts | 29/7/50 | 4 | T | 1 | Homicide |
| Malvern | Victory | Hoyts | 29/7/50 | 4 | T | 1 | Homicide |
| Yarraville | St. George | Suburban | 5/8/50 | 5 | T | 1 | Homicide |
| Williamstown | Shore | Hoyts | 5/8/50 | 5 | T | 1 | Homicide |
| Eltham | Plaza | Suburban | 12/8/50 | 6 | S | 2 | I Was a Male War Bride |
| Oakleigh | Paramount | Independent | 12/8/50 | 6 | T | 1 | Homicide |
| Box Hill | Rialto | Suburban | 19/8/50 | 7 | T | 2 | The Small Back Room |
| Chelsea | Plaza | Independent | 19/8/50 | 7 | W | 2 | Oh! You Beautiful Doll |
| Preston West | Rivoli | Independent | 26/8/50 | 8 | S | 2 | I Was a Male War Bride |
| North Melbourne | Loco | Independent | 2/9/50 | 9 | T | 2 | Pinky |
| North Richmond | Victoria | Independent | 9/9/50 | 10 | T | 2 | Adam and Evelyne |
| Coburg West | Progress | Independent | 18/11/50 | 20 | S | 2 | Pinky |
The 1950 Project 