William Friedkin, the director of "The Exorcist," declined to participate in the sequel, "The Heretic," which passed to John Boorman, but Friedkin will also be represented by a new production this summer: "Sorceror," an adventure melodrama scheduled to open Friday, June 24, at the K-B Flower, K-B Georgetown Square, K-B MacArthur, Landover Mall and Springfield Mall.

Coincidentally, "The Heretic" opens a week earlier. While Friedkin spurned a sequel to his biggest hit, the rather misleadingly titled "Sorceror" happens to be a remake of a foreign-language sensation of the mid-'50s, Henri-Georges Clouzot's spine-tingling "The Wages of Fear," which starred Yves Montand as one of four down-and-out Europeans who agree to ferry truckloads of nitroglycerin to the site of an oil well fire in the South American jungle.

Revived infrequently over the past dozen years or so and now apparently out of circulation, at least until "Sorceror" runs its course, "The Wages of Fear" has probably become a legendary classic. It was an unforgettable picture, uniquely frightening and uncompromisingly fatalistic. It appears that Friedkin may have embellished the original perilous premise with external threats like terrorist raids, which presumably rationalize a budget of several million. Walon Green, who cooked up "The Hellstrom Chronicle" and collaborated with Sam Peckinpah on "The Wild Bunch," did the screenplay for "Sorceror." Roy Scheider gets top billing in an international cast of male leads that includes Bruno Cremer, Francisco Rabal and Amidou.

The new Peckinpah feature, "Cross of Iron," a combat melodrama filmed in Yugoslavia and derived from a Willi Heinrich novel about Wehrmacht soldiers fighting the Red Army in the last months of World War II, is scheduled to open Friday, May 20, at the Jenifer and Springfield Mall. James Coburn is the principal warrior, the battle-hardened Sgt. Steiner.

Two units of the Roth's Tysons Corner will join the Avalon 1 in the first-run engagement of Joan Micklin Silver's "Between the Lines," opening next Wednesday, May 18. "Citizens Band," a comedy-melodrama about CB enthusiasts, reuniting two of the leads from "American Graffiti," Paul Le Mat and Candy Clark, arrives the same day at 16 theaters or drive-ins. An East German film, "Jacob the Liar," will also open on May 18 at the Dupont Circle, a week later than previously announced. The long-awaited "Billy Jack Goes to Washington" gets under way today at the K-B Cerberus, Flower and Janus.

Paramount is reissuing "The Godfather" and "The Godfather, Part II" this summer on a marathon double-bill program. The local engagement begins Wednesday, June 1, at Keith's, K-B Bethesda, Landover Mall and the State. Figures released by the company reveal considerable disparity between the box-office performances of the films. According to paramount, "The Godfather" has returned worldwide rentals of $137 million, while the sequel has returned $28 million domestically. If these figures can be trusted, it appears that "Godfather II" may still be struggling toward the break-even point.