In the movie, Hopkins and O'Donoghue both fall victim to the demon baal's devilish influence.
"The name of many deities of the Semitic peoples" [Klein], late 14c., Biblical use is from Hebrew Ba'al, literally "owner, master, lord," from ba'al "he took possession of," also "he married;" related to Akkadian Belu (source of Hebrew Bel), name of Marduk. Also related to the first element in Beelzebub. Used figuratively for any "false god."
lord. (1.) The name appropriated to the principal male god of the Phoenicians. It is found in several places in the plural BAALIM (Judg. 2:11; 10:10; 1 Kings 18:18; Jer. 2:23; Hos. 2:17). Baal is identified with Molech (Jer. 19:5). It was known to the Israelites as Baal-peor (Num. 25:3; Deut. 4:3), was worshipped till the time of Samuel (1 Sam 7:4), and was afterwards the religion of the ten tribes in the time of Ahab (1 Kings 16:31-33; 18:19, 22). It prevailed also for a time in the kingdom of Judah (2 Kings 8:27; comp. 11:18; 16:3; 2 Chr. 28:2), till finally put an end to by the severe discipline of the Captivity (Zeph. 1:4-6). The priests of Baal were in great numbers (1 Kings 18:19), and of various classes (2 Kings 10:19). Their mode of offering sacrifices is described in 1 Kings 18:25-29. The sun-god, under the general title of Baal, or "lord," was the chief object of worship of the Canaanites. Each locality had its special Baal, and the various local Baals were summed up under the name of Baalim, or "lords." Each Baal had a wife, who was a colourless reflection of himself. (2.) A Benjamite, son of Jehiel, the progenitor of the Gibeonites (1 Chr. 8:30; 9:36). (3.) The name of a place inhabited by the Simeonites, the same probably as Baal-ath-beer (1 Chr. 4:33; Josh. 19:8).