Deal-making, blackmail, sexual obsession, and terrorism at the Cannes Film Festival--in a mostly readable, relatively un-sleazy mix of film-biz motifs that leans rather heavily (probably too heavily for the fan-mag audience) on matters of takeovers, breakaways, and financing. All these are on the mind of charismatic studio exec Teddy Kenrick, who has come to Cannes to gather allies for his intended breakaway from his Big Studio (not entirely unlike the recent United Artists brouhaha), to sleuth out the shady financing in the Studio's past, and to brave out the premiere of late, great Pedro Lehman's last film--an unsaveable turkey. Lehman's widow, ex-superstar Siri, is in Cannes too; she's here to negotiate her return to the screen and to escape from the obsessed worshipper who forced her to retire and drove Pedro to suicide, gangster Nicky Deane. (Deane--who's also been blackmailing Kenrick--repellently shows up, however, forcing an ugly confrontation with terrified, kidnapped Sift.) But by far the most appealing chunk of plot belongs to has-been alcoholic actor Rod Donner, a poor man's John Wayne who has finally found the script that'll give him class; and you'll care as Donner works hard to control himself and make it happen, with a P-R assist from his ex-wife--sleek super-flak Rayna Tate (who's now bedding down with Kenrick). It's heroic Donner, unfortunately, who dies when all the leading characters are taken hostage in a hotel room by a seedy French terrorist. . . after which the novel loses steam and focuses entirely on Kenrick's complicated business deals. So: erratic stuff, somewhere between formula multi-plotted nonsense and real-Hollywood intrigue--generally professional, intermittently involving, and (no small praise) never repulsive.