OPINION
FRIEDMAN, District Judge:
*656Pragedio Espinoza-Valdez appeals his convictions for conspiracy to import and conspiracy to distribute marijuana. He argues that the evidence presented at trial was insufficient to support either conviction and that the district court therefore erred in denying his motion for acquittal notwithstanding the verdict. We agree and reverse the two conspiracy convictions.1
I. STANDARD OF REVIEW AND LEGAL AUTHORITY
We review de novo whether, "after viewing the evidence in the light most favorable to the prosecution, any rational trier of fact could have found the essential elements of the crime beyond a reasonable doubt." United States v. Nevils , 598 F.3d 1158, 1163-64 (9th Cir. 2010) (en banc); accord United States v. Grovo , 826 F.3d 1207, 1213-14 (9th Cir. 2016) ; United States v. Egge , 223 F.3d 1128, 1131 (9th Cir. 2000). Even on this deferential standard, we conclude that the government presented insufficient evidence that Espinoza-Valdez entered into a conspiratorial agreement to distribute or import marijuana. The district court therefore erred in denying Espinoza-Valdez's motion for judgment of acquittal.
The elements of conspiracy are "(1) an agreement to accomplish an illegal objective, and (2) the intent to commit the underlying offense." United States v. Moe , 781 F.3d 1120, 1124 (9th Cir. 2015) ; see also United States v. Loveland , 825 F.3d 555, 559 (9th Cir. 2016) ; United States v. Herrera-Gonzalez , 263 F.3d 1092, 1095 (9th Cir. 2001) ; United States v. Lennick , 18 F.3d 814, 818 (9th Cir. 1994). To be convicted of conspiracy, the defendant must have joined the agreement knowing its purpose and intending to help accomplish that purpose. See United States v. Mincoff , 574 F.3d 1186, 1192 (9th Cir. 2009). The conspiratorial agreement may be proved by direct or circumstantial evidence. See Loveland , 825 F.3d at 561-62 ; Mincoff , 574 F.3d at 1192. It is not necessary that the conspirators made a formal or express agreement or that they agreed on every detail of the conspiracy. See Mincoff , 574 F.3d at 1194-95 ; United States v. Melvin , 91 F.3d 1218, 1224 (9th Cir. 1996). Rather, the agreement may be inferred from the defendants' acts pursuant to the scheme and other circumstantial evidence. See Grovo , 826 F.3d at 1216 ; United States v. Lapier , 796 F.3d 1090, 1095 (9th Cir. 2015) ; Mincoff , 574 F.3d at 1192. The government has the burden of proving beyond a reasonable doubt the creation and existence *657of the conspiratorial agreement, as well as the defendant's entry into that agreement. See Loveland , 825 F.3d at 557, 561 ; Moe , 781 F.3d at 1124 ; Lennick , 18 F.3d at 818, 820. Furthermore, "[t]he government has the obligation to establish not only the opportunity but also the actual meeting of minds. Mere association and activity with a conspirator does not meet the test." Lapier , 796 F.3d at 1095 ; see also Lennick , 18 F.3d at 818 ("[S]imple knowledge, approval of, or acquiescence in the object or purpose of a conspiracy, without an intention and agreement to accomplish a specific illegal objective, is not sufficient.").
II. FACTUAL BACKGROUND
In this case, the government presented evidence at trial that U.S. Border Patrol agents had observed three men on a mountaintop in the Vaiva Hills area of Arizona. Two of them were communicating with one another. The third man, Espinoza-Valdez, was initially observed some distance away sitting under a tree. Later, he was observed walking behind one of the other men and carrying a backpack. Upon seeing the agents, Espinoza-Valdez dropped the Motorola radio he was carrying and ran. The agents apprehended him and found a Motorola battery clip, radio batteries, toilet paper, wet wipes, and food in his backpack, to which carpet shoes were attached. One of the agents testified that carpet shoes are used by both drug couriers and undocumented immigrants to avoid leaving footprints while passing through the area. The agents also located a nearby campsite with sleeping bags, water jugs, and additional food supplies. They did not find any drugs in the area.2
In addition, U.S. Border Patrol Commander Bobby Garcia testified as an expert on drug trafficking organizations as follows: Drug trafficking organizations smuggle marijuana into the United States using groups of five to ten men who hike across the desert carrying marijuana in backpacks. These backpackers are led by guides who communicate by cell phone or radio with scouts who camp along the route and monitor law enforcement movements. Drug smugglers often use Motorola brand radios with sophisticated encryption capabilities and carry carpet shoes to disguise their footprints. The month of October-when Espinoza-Valdez was apprehended-is part of the fall "drug-smuggling season," and the Vaiva Hills area is a known drug-smuggling corridor. Drug traffickers control the area and would not allow others to move through it, and the circumstances surrounding Espinoza-Valdez's apprehension were consistent with him being a drug trafficking scout.
The government also presented evidence that, approximately four months prior to the events giving rise to the instant case, U.S. Border Patrol agents had apprehended Espinoza-Valdez in the same Vaiva Hills area. At that time, Espinoza-Valdez told the agents that he and others had entered the United States and were backpacking marijuana across the desert. The agents did not locate any backpacks of marijuana. Espinoza-Valdez was released and not charged with any criminal offense. This evidence was admitted at trial under Federal Rule of Evidence 404(b), and the court gave a limiting instruction.
III. DISCUSSION
Despite the evidence of Espinoza-Valdez's presence with two unknown men *658in a known drug-smuggling corridor close to the Mexican border near what appeared to be a camp for drug trafficking scouts, as well as the seizure of items that were suspicious in this context, there was insufficient evidence for a jury to find beyond a reasonable doubt that Espinoza-Valdez entered into a conspiratorial agreement to import or distribute marijuana. The government's case rested almost exclusively on the expert testimony regarding drug traffickers' use of scouts to facilitate the transportation of marijuana through the Vaiva Hills area. The government presented no evidence of drugs that actually passed through or were intended to pass through that area under Espinoza-Valdez's watch. Nor did the government present evidence of any specific individuals with whom Espinoza-Valdez allegedly conspired. There simply is no evidence as to what (if anything) was specifically agreed to, who agreed to it, or what any agreement was intended to accomplish.3 Given the dearth of evidence of an agreement to import or distribute marijuana between Espinoza-Valdez and the two unknown men observed on the mountain-or anyone else-the government has not met its burden of proving his participation in a conspiracy beyond a reasonable doubt. See Loveland , 825 F.3d at 557 ; Lapier , 796 F.3d at 1095 ; United States v. Penagos , 823 F.2d 346, 347-50 (9th Cir. 1987).4
Furthermore, we have long held that drug courier profile evidence such as that admitted here is admissible only for limited purposes. See United States v. Webb , 115 F.3d 711, 715 (9th Cir. 1997), abrogated on other grounds by United States v. Hankey , 203 F.3d 1160, 1169 n.7 (9th Cir. 2000).5 Drug courier profile testimony is inherently prejudicial because of the potential it has for including innocent *659citizens as profiled drug couriers and because simply matching a defendant to a drug profile may unfairly suggest to the jury that otherwise innocuous conduct or events demonstrate criminal activity. See United States v. Cordoba , 104 F.3d 225, 229-30 (9th Cir. 1997) ; United States v. Lim , 984 F.2d 331, 334-35 (9th Cir. 1993) ; United States v. Beltran-Rios , 878 F.2d 1208, 1210 (9th Cir. 1989) ; see also United States v. White , 890 F.2d 1012, 1014 (8th Cir. 1989) ; United States v. Hernandez-Cuartas , 717 F.2d 552, 555 (11th Cir. 1983).6 A drug expert's testimony cannot substitute for witnesses who actually observed or participated in the illegal activity. Nor can it be permitted to so submerge the factual evidence that its unfair prejudicial effect substantially outweighs any probative value it might have. See Rogers v. Raymark Indus., Inc. , 922 F.2d 1426, 1430-31 (9th Cir. 1991) ; White , 890 F.2d at 1013-14 ; Hernandez-Cuartas , 717 F.2d at 555. The government may not rely on expert testimony of drug courier profiles alone to establish guilt. Yet here, Garcia's broad expert testimony-describing the structure of drug trafficking organizations and the drug scout profile and linking Espinoza-Valdez to that profile-was the crux of the government's case.
While it is possible, perhaps even probable, that Espinoza-Valdez was on the mountaintop to act as a scout for drug traffickers, a reasonable suspicion or probability of guilt is not enough. Guilt, according to the basic principles of our jurisprudence, must be established beyond a reasonable doubt. Here, it was not: Viewing the entirety of the evidence in the light most favorable to the government, there was insufficient evidence upon which a reasonable mind might fairly find the existence of a conspiracy to import or distribute marijuana-or of Espinoza-Valdez's agreement to join such a conspiracy-beyond a reasonable doubt. See Grovo , 826 F.3d at 1213-14 ; Nevils , 598 F.3d at 1163-64 ; Egge , 223 F.3d at 1131.
The district court's judgment with respect to the convictions for conspiracy to import and conspiracy to distribute marijuana is REVERSED.