D: Edward L. Cahn. Marshall Thompson, Shawn Smith, Kim Spalding, Ann Doran, Dabbs Greer. The second spaceship to Mars heads for Earth with the sole survivor of the first expedition, accused of murdering his crewmates--but the real killer is a Martian monster (Ray "Crash'' Corrigan), which has crept aboard the returning ship. ALIEN owes a lot to this tidy, suspenseful, but underproduced movie, scripted by sci-fi writer Jerome Bixby.

D: Gordon Douglas. James Whitmore, Edmund Gwenn, Joan Weldon, James Arness, Onslow Stevens. First-rate '50s sci-fi about giant ant mutations running wild in the Southwest. Intelligent script (by Ted Sherdeman, from George Worthing Yates' story) extremely well directed, with memorable climax in L.A. sewers. Fess Parker has small but memorable role. Look fast for Leonard Nimoy at a teletype machine.

D: Christian Nyby. Kenneth Tobey, Margaret Sheridan, Robert Cornthwaite, Douglas Spencer, James Arness, Dewey Martin, William Self, George Fenneman. Classic blend of science-fiction and horror, loosely based on John W. Campbell, Jr.'s Who Goes There? Scientists at lonely Arctic outpost dig up alien (Arness) from the permafrost and must fight for their lives when it's accidentally thawed. Tense direction (often credited to producer Howard Hawks), excellent performances, eerie score by Dimitri Tiomkin. Screenplay by Charles Lederer. Watch out for 81m. reissue prints. Remade in 1982.

D: George Pal. Rod Taylor, Alan Young, Yvette Mimieux, Sebastian Cabot, Tom Helmore, Whit Bissell, Doris Lloyd. H. G. Wells' fantasy reduced to comic book level, but still entertaining, with Taylor as single-minded turn-of-the-20th-century London scientist who invents time-travel device and has vivid experiences in the future. Oscar-winning special effects. Remade in 1978 (for TV) and 2002.